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Aluminij i njegove legure nalaze mnoge primjene u strojarstvu zbog svojih prikladnih svojstava kao što su povoljna specifična čvrstoća i korozijska postojanost. Aluminij se podvrguje različitim tehnologijama obrade kako bi dobili bolja svojstva te prilagodili materijal okolišu u kojem će biti eksploatiran. Materijali u eksploataciji podvrgnuti su različitim vrstama trošenja, a jedno od njih je i erozijsko trošenje. U ovom radu ispitani su uzorci aluminija toplo valjanog, hladno kovanog i uzorci nastali kutnom ekstruzijom u uvjetima erozijskog trošenja te su na kraju izneseni zaključci. Aluminum and its alloys find many applications in mechanical engineering due to their suitable properties such as favorable specific strength and corrosion resistance. Aluminum is subjected to different processing technologies in order to obtain better properties and adapt the material to the environment in which it will be exploited. Materials in exploitation are subjected to different types of wear, one of which is erosion wear. In this paper, samples of hot-rolled, cold-forged aluminum and samples created by angular extrusion under conditions of erosion wear were tested, and conclusions were presented at the end.

Ovaj diplomski rad koncipiran je tako da se je konstruirala vlastita konstrukcija hibridnog okvira bicikla s osnovnim dimenzijama baziranim na opsežnom istraživanju izvora. Na samom početku objašnjene su glavne razlike između bicikala, te su pobrojane glavne vrste okvira bicikla danas u uporabi. Vlastitim dizajnom pojedinih oblika cijevi okvira, došlo se do dva finalna modela koja se geometrijom temelje na osnovnom štapnom modelu/konceptu. U središnjem dijelu razmatrale su se analize konačnim elementima s obzirom na tri najčešća materijala korištena pri izradi bicikala. Slučajevi opterećenja u tim analizama izvedeni su tako da se čim više pokušaju približiti stvarnim eksploatacijskim uvjetima okvira bicikla tijekom vožnje. Dobivenim rezultatima odabran je najadekvatniji materijal koji se je zatim primijenio na numeričke analize vlastita dva dizajna okvira, pod već spomenutim opterećenjima. Na kraju je odabran i objašnjen superiorniji okvir hibridnog bicikla preko rezultata numeričkih analiza. This master thesis is based on idea of constructing a new type of hybrid bicycle frame with basic dimensions acknowledged from an extensive research of many sources. At the very beginning, the main differences between bicycles are explained. After that, some of the main types of bicycle frames in use today are listed. With perception of general geometry of concept model, two new bicycle frames were constructed. There are small differences between their design but the main change are shapes and cross sections of tubes. In the central part, few finite element analysis were conducted with usage of the three most common materials used in the bicycles manufacturing. The load cases in these analysis were performed to simulate actual operating conditions of the bicycle frame during riding. Based on the obtained results, the most adequate material was selected and then was applied to the numerical analysis of two frame designs, under the certain load cases. Finally, a superior hybrid bike frame was selected and explained with brief conclusion based on FEA analysis.

Tema ovog diplomskog bila je proučiti utjecaj alata na mehanička svojstva zavarenog spoja kod točkastog zavarivanja trenjem rotirajućim alatom. U prvom dijelu rada opisan je postupak zavarivanja trenjem rotirajućim alatom, s time da je stavljen fokus na točkasto zavarivanje trenjem rotirajućim alatom. Ukratko je opisana povijest postupka, opisane su faze postupka, utjecajni čimbenici, prednosti i nedostaci. Navedeni su materijali koji se mogu zavarivati točkastim zavarivanjem trenjem rotirajućim alatom te su navedeni primjeri iz prakse gdje se koristi navedena vrsta zavarivanja. U drugom dijelu diplomskog rada provedeno je točkasto zavarivanje trenjem rotirajućim alatom na limovima od aluminijeve legure. Prilikom zavarivanja korištena su 2 tipa alata za zavarivanje te su mijenjane brzine rotacije alata i vrijeme trajanja procesa zavarivanja. Limovi koji su zavareni su podvrgnuti smičnom ispitivanju te je analiziran rezultat ispitivanja. Na kraju rada donesen je zaključak o utjecaju alata na mehanička svojstva zavarenog spoja. The topic of this thesis was to study the influence of tool on the mechanical properties of the welded joint during the friction stir welding. The first part of this master's thesis presents the friction welding procedure with a rotating tool, with the main focus being on spot welding with a rotating friction tool. There can be found a short procedure history brief, all stages of the procedure, influencing factors, advantages and disadvantages. The materials that can be welded by friction stir spot welding with a rotating tool are listed, and also examples from practice were mentioned. In the second part of the thesis, spot welding with a friction rotating tool was performed on aluminum sheets. During welding, 2 types of welding tools were used, and the rotation speeds of the tool and the duration of the welding process were changing. The welded sheets were subjected to a static tensile test and the result was analyzed. Finally, the graduate thesis provides a conclusion about the influence of tool on the mechanical properties of the welded joint.

U teorijskom dijelu rada opisana je podjela aluminijskih legura, njihove karakteristike i problematika zavarljivosti aluminijskih legura s posebnim osvrtom na primjenu aluminijskih legura u brodogradnji. Detaljno je opisan TIG postupak zavarivanja te je objašnjena klasifikacija osnovnih vrsta spojeva koji se primjenjuju pri izradi brodskih konstrukcija. U posljednjem dijelu teorijskog rada dan je pregled pripreme spojeva za zavarivanje aluminijskih legura prema normi HRN EN ISO 9692-3. U eksperimentalnom dijelu rada odabrana je tehnologija zavarivanja aluminijske legure 6082 T6. Strojnom obradom sukladno normi HRN EN ISO 9692-3 pripremljene su dvije cijevi. Provedeno je zavarivanje radnih komanda AC TIG postupkom. Naposljetku su provedena ispitivanja radiografskom metodom, statično-vlačni pokus i ispitivanje savijanjem te je izvršena makroskopska analiza. Na temelju dobivenih rezultata eksperimentalnog rada donesen je zaključak. The theoretical part of this thesis deals with the division of the aluminum alloys, their characteristics and weldability problems, with special reference to the application of aluminum alloys in shipbuilding. The TIG welding process is described in detail. Moreover, the classification of the basic types of joints used in the construction of the ship structures is explained. An overview of the preparation of joints for welding aluminum alloys according to the HRN ISO 9692-3 standard is given in the last part of the theoretical work. In the experimental part the suitable welding technology has been chosen for welding aluminum alloy 6082 T6. Two pipes were prepared by machining accordingly to the HRN ISO 9692-3. Butt welding of pipe was done using the AC TIG technology. Ultimately, tests were carried out using the radiographic method, static tensile test and bending test, along with performing macroscopic analysis. Based on the obtained results of the experimental work, a conclusion was made.

Tema ovog rada je „Analiza utjecaja zaštitnog plina na profil penetracije kod MIG zavarivanja aluminija“ Teorijski dio rada opisuje svojstva aluminija i aluminijskih legura, njihovu primjenu i proizvodnju. Obrađene su tehnologije zavarivanja aluminija te ukratko opisan MIG postupak zavarivanja aluminija. Detaljno su opisani zaštitni plinovi korišteni kod zavarivanja aluminija – argon, helij te plinske mješavine argona i helija. Eksperimentalni dio rada sastoji se od pripreme 3 uzorka aluminijske legure 5083 debljine 10 mm, izvođenja postupka MIG zavarivanja pulsnim lukom i istim parametrima zavarivanja te analizom dobivenih rezultata zavarivanja. Zavareni kutni spojevi podvrgnuti su vizualnoj i penetrantskoj kontroli zavara, izradi makroizbrusaka i mjerenju geometrije. Analizom rezultata ispitivanja utvrđen je utjecaj različitih plinskih mješavina na profil penetracije. Pokazana je razlika u iznosu dubine i obliku penetracije u ovisnosti o postocima argona i helija u zaštitnoj plinskoj mješavini. The topic of this paper is "Analysis of shielding gas influence on penetration profile at MIG welding of aluminum." The theoretical part of the thesis describes the properties of aluminum and aluminum alloys, their applications, and production. Welding technologies of aluminum are discussed, and the MIG welding process of aluminum is described. The protective gases used in aluminum welding - argon, helium, and gas mixtures of argon and helium - are described in detail. The experimental part of the paper consists of preparing three samples of 10 mm thick aluminum alloy 5083, performing the MIG welding process with a spray arc and the same welding parameters and analyzing the obtained welding results. The welded corner joints were visually and penetrant inspected, and macro examinations were done, followed by measuring the geometry. The analysis of the results showed the influence of different shielding gas mixtures on penetration profile. The difference was shown in the depth and shape of the penetration, depending on the percentage of argon and helium in the shielding gas mixture.

Cilj ovoga rada bila je analiza zavarenog spoja legure aluminija oznake EN AW-5083. To je gnječena legura aluminija s najvećim udjelom magnezija kao legirnog elementa. Zavareni spoj izveden je TIG tehnikom spajanja uz prethodno predgrijavanje na 150 °C. U teorijskom dijelu obrađene su vrste aluminija i njegovih legura te načini zavarivanja istih. Objašnjene su moguće pogreške koje se mogu pojaviti tijekom ili nakon zavarivanja. U eksperimentalnom dijelu rada analizirana je makrostruktura zavarenog spoja, te mikrostruktura osnovnog materijala, zone utjecaja topline i metala zavara. Osim toga provedeno je ispitivanje mikrotvrdoće HV0,2, statičko vlačno i savojno ispitivanje. U strukturi nisu uočene nikakve nepravilnosti koje bi negativno utjecale na kvalitetu zavarenog spoja. U odnosu na mikrotvrdoću osnovnog materijala (oko 68 HV0,2), mikrotvrdoća u ZUT-u i metalu zavara je viša za oko 20 %.Vrijednost vlačne čvrstoće u osnovnom materijalu je 330 MPa, a u metalu zavara 280 MPa. Tijekom savojnog ispitivanja do kuta od 180° nisu uočene pukotine u zavarenom spoju. The aim of this work was the analysis of the welded joint of aluminum alloy EN AW-5083. It is a wrought aluminum alloy with the highest proportion of magnesium as an alloying element. The welded joint was made using the TIG joining technique with preheating to 150 °C. In the theoretical part, the types of aluminum and its alloys and methods of welding them are covered. Possible errors that may occur during or after welding are explained. In the experimental part of the work, the macrostructure of the welded joint was analyzed, as well as the microstructure of the base material, the heat-affected zone and the weld metal. In addition, a microhardness test of HV0.2, a tensile and bend test, was performed. No irregularities were observed in the structure that would negatively affect the quality of the welded joint. In relation to the microhardness of the base material (about 68HV0.2), the microhardness in ZUT and weld metal is higher by about 20%. The value of the tensile strength in the base material is 330 MPa, and in the weld metal 280 MPa. During the bending test, no cracks were observed in the welded joint up to an angle of 180°.

U ovom su radu obrađeni zahtjevi norme HRN EN ISO 25239 za procjenu kvalitete spojeva načinjenih postupkom zavarivanja trenjem uz miješanje. Rad se sastoji od teorijskog i eksperimentalnog dijela. U teorijskom dijelu rada ukratko su opisani pojmovi poput povijesti, parametara, prednosti, nedostataka i primjene postupka zavarivanja trenjem uz miješanje (eng. Friction stir welding (FSW)). Opisan je princip rada te detaljno obrađena geometrija radnog alata. Također, navedena su i opisana ograničenja postupka kod zavarivanja aluminija. U eksperimentalnom dijelu ispitivan je uzorak načinjen od aluminijeve legure AlSi12 postupkom zavarivanja trenjem uz miješanje. Odrađena su ispitivanja prema zahtjevima norme HRN EN ISO 25239, kako bi se ocijenila kvaliteta zavarenog spoja. Dobiveni rezultati su analizirani te je ocijenjena primjenjivost postupka pri zavarivanju aluminijevih legura. In this paper, the requirements of the HRN EN ISO 25239 standard for assessing the quality of joints made by the friction stir welding process are discussed. The paper consists of a theoretical and an experimental part. In the theoretical part of the work, terms such as history, parameters, advantages, disadvantages and applications of friction stir welding (FSW) are briefly described. The working principle is described and the geometry of the working tool is detailed. Limitations of the aluminum welding procedure are also listed and described. At the end of the theoretical part, each norm was interpreted separately. In the experimental part, a sample made of aluminum alloy AlSi12 was tested using friction stir welding. Tests were performed according to the requirements of HRN EN ISO 25239, in order to evaluate the quality of the welded joint. The obtained results were analyzed and the applicability of the procedure for welding aluminum alloys was assessed.

U ovom radu opisana su opća svojstva aluminija i njegovih legura te značajan utjecaj na mehanička, fizikalna i kemijska svojstva metalnih materijala, točnije aluminija. Jedan od važnijih utjecaja nakon plastične deformacije odnosi se na promjene postojanosti metalnih materijala. Aluminij u odnosu na druge metale ima puno prednosti poput male mase, velike otpornosti na koroziju, mogućnosti recikliranja, jednostavnost obrade, itd. Poseban naglasak je stavljen na pozitivan, ali i negativan utjecaj plastične deformacije na korozijsku postojanost, koja naravno ovisi o načinu i temperaturi procesa te o vrsti materijala, odnosno njegovoj čvrstoći. Niska čvrstoća aluminija poboljšava se legiranjem. Plastična deformacija definirana je kao kretanje dislokacija kroz kristalnu rešetku materijala koja nastaje zbog naprezanja. Povećanjem stupanja deformacije, veća je i gustoća dislokacija u strukturi materijala. Veća je tvrdoća, ali je manja otpornost na koroziju. Povećanjem debljine površinskoga oksidnog sloja elektrokemijskim putem (eloksiranjem), povećava se otpornost aluminija prema koroziji. Tanak sloj koji nastaje, oksidni sloj, je porozan, može se obojiti i prevući organskim bojama. Boja trajno ostaje u oksidnome sloju jer se pore se zatvaraju na povišenoj temperaturi. Na korozijsku postojanost aluminijskih legura utječe u stupanj deformacije materijala. Ovaj utjecaj veći je kod nekih legura sa magnezijem (serija 5000) i silicijem (serija 6000) te se postižu bolja mehanička svojstva u slučaju toplog plastičnog oblikovanja. Primjena aluminijskih legura ograničena je pri povišenim temperaturama zbog niske temperature tališta aluminija (660 °C). Uporaba njihovih legura dozvoljena je do temperature od 150 °C do najviše 200 °C. This paper describes the general properties of aluminum and its alloys, significant influence on the mechanical, physical and chemical properties of metal materials, specifically aluminum. One of the morst important influences after plastic deformation refers to changes in the durability of metallic materials. Compared to other metals, aluminum has many advantages, such as low weight, high resistance to corrosion, recyclability, ease of processing, etc. Special emphasis is placed on the positive and negative impact of plastic deformation on corrosion resistance, which of course, depends on the method and temperature process and on the type of material, i.e. its strength. The low strength of aluminum is improved by alloying. Plastic deformation is defined as the movement of dislocations through the crystal lattice of the material that occurs due to strain. By increasing the rate of deformation, the density of dislocations in the material structure also increases. It has higher solidity, but lower resistance to corrosion. Aluminum's resistance to corrosion increases by increasing the thickness of the surface oxide layer by electrochemical means (anodization). The resulting thin layer, the oxide layer, is porous and can be painted and coated with organic dyes. The color remains permanently in the oxide layer because the pores close at elevated temperatures. The corrosion resistance of aluminum alloys is affected by the degree of deformation of the material. This influence is greater in some alloys with magnesium (series 5000) and silicon (series 6000), and better mechanical properties are achieved in the case of hot plastic forming. The use of aluminum alloys is limited at elevated temperatures due to the low melting point of aluminum (660 °C). Their use is permitted up to a temperature of 150 °C to a maximum of 200 °C

Bijeli lim i aluminij su metalni materijali koji se upotrebljavaju za izradu ambalaže i pakiranje namirnica. Bijeli lim je kombinacija čeličnog lima i kositra, dok se aluminijska ambalaža proizvodi od vrlo čistog aluminija. Zbog brojnih dobrih osobina limenke od bijelog lima i aluminija koriste se za pakiranje različitih vrsta namirnica. Cilj ovog rada je definirati i objasniti bijeli lim i aluminij, njihove pozitivne i negativne osobine, dvodijelne i trodijelne limenke te dati primjere namirnica koje se pakiraju u ovu ambalažu. Tin plate and aluminum are metal materials that are used to make packaging for food. Tin plate is a combination of steel sheet and tin, while aluminum packaging is made of very pure aluminum. Due to their many good features, tin cans and aluminum cans are used for the packaging of different types of food. The goal of this paper is to define and explain tin plate and aluminum, their positive and negative characteristics, two-part and three-part cans, and to give examples of foods that are packed in these materials.

Aluminij je jedan od najzastupljenijih metala u polju strojarstva koji osim niske gustoće i visoke korozijske postojanosti ima značajna svojstva električne i toplinske vodljivosti. Problem sirovog aluminija leži u vidu niskih vrijednosti čvrstoće i tvrdoće, mehaničkih svojstava koje su presudne prilikom izrada konstrukcijskih i strojnih dijelova. Kombinacijom legiranja te različitim parametrima toplinske obrade moguće je povećati otpornost i deformabilnost aluminija. U radu su opisana svojstva aluminij i aluminijevih legura, s posebnim naglaskom na toplinsko obradive legure, te pregled postupaka ispitivanja mehaničkih svojstava. U eksperimentalnom dijelu provedena je analiza uzoraka aluminijeve legure u polaznom stanju, te nakon dvije kombinacije toplinske obrade gdje su praćene promjene mehaničkih svojstava i mikrostrukture. Komentirani su rezultati te su doneseni određeni zaključci. Aluminum is one of the most common metals in the field of mechanical engineering, which, in addition to its low density and high corrosion resistance, has significant properties of electrical and thermal conductivity. The problem of raw aluminum lies in its low values of strength and hardness, mechanical properties that are crucial when making structural and machine parts. By combining alloying and different heat treatment parameters, it is possible to increase the resistance and deformability of aluminum. The paper describes the properties of aluminum and aluminum alloys, with a special emphasis on heat-treatable alloys, and an overview of the mechanical properties testing procedures. In the experimental part, an analysis of the aluminum alloy samples was carried out in the initial state, and after two combinations of heat treatment, where changes in mechanical properties and microstructure were monitored. The results were analyzed and certain conclusions were made.

As the microelectronic industry develops, components that can perform several different tasks receive increasingly more attention, resulting in multifunctional materials being highly sought after. ▫$Al_2O_3$▫ is widely present in electronic applications as a protective coating or as an electrical and thermal insulator due to its mechanical and thermal stabilities and chemical inertness. ▫$Al_2O_3$▫ is also an important dielectric material, with high resistivity and stable permittivity over a wide range of temperatures and electric fields, but its modest permittivity necessitates large effective areas or extremely thin layers when a large capacitance is desired. Composites consisting of discrete conducting phases within an insulating matrix can produce large capacitance via Maxwell–Wagner polarization. In this work, ▫$Al_2O_3$▫/Al composite thick films with different volume ratios of Al were prepared using the aerosol deposition method. A relative dielectric permittivity (εr′) of 800 at 1 MHz was achieved at 27 vol% of Al, a sixty-sevenfold enhancement compared to ▫$Al_2O_3$▫. On the other hand, dielectric losses, tan(δ), at 1 MHz increased from 0.01 for ▫$Al_2O_3$▫ up to 0.58 for the composite with 27 vol% of Al. A finite-element model of the composites was implemented, supporting the nonlinear electrical behavior of the composites as function of vol% of Al. Our results show novel possibilities for the applications of ▫$Al_2O_3$▫-based materials in the microelectronic industry, especially for temperature-sensitive applications, for which the integration strengths of aerosol deposition are valuable.

U sklopu ovog rada ispitivano je elektrokemijsko ponašanje aluminija u otopinama limunske i perklorne kiseline pri različitim pH vrijednostima, bez i s dodatkom natrijevog poli(stirensulfonata). Cilj istraživanja je određivanje utjecaja prisutnosti natrijevog poli(stiren-sulfonata) u otopinama, na kinetičke korozijske parametre. Za određivanje kinetičkih korozijskih parametara korišena je metoda potenciodinamičke polarizacije. Za karakterizaciju površine aluminija prije elektrokemijskih mjerenja korištena je metoda mikroskopije atomskih sila. Određen je utjecaj pH vrijednosti otopina na kinetičke korozijske parametre. S obzirom na utjecaj pasivnih oksidnih filmova na koroziju aluminija ispitan je utjecaj prisutnosti polielektrolita na pasivaciju aluminija i potencijalno inhibitorsko djelovanje polielektrolita. Dokazano je da prisutnost natrijevog poli(stiren-sulfonata) utječe na kinetičke korozijske parametre. U otopinama s limunskom kiselinom prisutnost polielektrolita ima sinergijski efekt, pojačava koroziju aluminija te djeluje na stabilnost oksidnog filma na površini metala. U otopinama s perklornom kiselinom vidljiv je inhibicijski utjecaj, ali i adsorpcija polielektrolita na površinu aluminija što utječe na stabilnost oksidnog filma. In this thesis, electrochemical behaviour of aluminum in citric and perchloric acid solutions, at different pH values, with or without added sodium poly(styren sulfonate) was studied. The goal of the research was determining the impact of presence of sodium poly(styren sulfonate) in solutions on kinetic corrosion parameters. The potentiodynamic polarization method was used for that purpose. The atomic force microscopy was used to characterize the aluminum surface before electrochemical measurements. The influence of solution pH on kinetic corrosion parameters was determined. Considering the influence of passive oxide films on the corrosion of aluminum, the influence of the presence of polyelectrolytes on the passivation of aluminum and the potential inhibitory effect of polyelectrolytes was investigated. The presence of sodium poly(styrene sulfonate) has been shown to affect kinetic corrosion parameters. In solutions with citric acid, the presence of polyelectrolytes has a synergistic effect, enhances the corrosion of aluminum and affects the stability of the oxide film. In solutions with perchloric acid, the inhibitory effect is visible, but also the adsorption of polyelectrolytes on the aluminum surface, which affects the stability of the oxide film.

The use of wood-based materials in building and construction is constantly increasing as environmental aspects and sustainability gain importance. For structural applications, however, there are many examples where hybrid material systems are needed to fulfil the specific mechanical requirements of the individual application. In particular, metal reinforcements are a common solution to enhance the mechanical properties of a wooden structural element. Metal-reinforced wood components further help to reduce cross-sectional sizes of load-bearing structures, improve the attachment of masonry or other materials, enhance the seismic safety and tremor dissipation capacity, as well as the durability of the structural elements in highly humid environments and under high permanent mechanical load. A critical factor to achieve these benefits, however, is the mechanical joint between the different material classes, namely the wood and metal parts. Currently, this joint is formed using epoxy or polyurethane (PU) adhesives, the former yielding highest mechanical strengths, whereas the latter presents a compromise between mechanical and economical constraints. Regarding sustainability and economic viability, the utilization of different adhesive systems would be preferable, whereas mechanical stabilities yielded for metal-wood joints do not permit for the use of other common adhesive systems in such structural applications. This study extends previous research on the use of non-thermal air plasma pretreatments for the formation of wood-metal joints. The plasma treatments of Norway spruce [Picea abies (L.) Karst.] wood and anodized (E6/EV1) aluminum AlMgSi0.5 (6060) F22 were optimized, using water contact angle measurements to determine the effect and homogeneity of plasma treatments. The adhesive bond strengths of plasma-pretreated and untreated specimens were tested with commercial 2-component epoxy, PU, melamine-urea formaldehyde (MUF), polyvinyl acetate (PVAc), and construction adhesive glue systems. The influence of plasma treatments on the mechanical performance of the compounds was evaluated for one selected glue system via bending strength tests. The impact of the hybrid interface between metal and wood was isolated for the tests by using five-layer laminates from three wood lamellae enclosing two aluminum plates, thereby excluding the influence of congeneric wood-wood bonds. The effect of the plasma treatments is discussed based on the chemical and physical modifications of the substrates and the respective interaction mechanisms with the glue systems. Nasl. z nasl. zaslona. Opis vira z dne 18. 1. 2022. Objavljeno na spletu 17. 1. 2022. Št. prispevka 796474. Bibliografija: str. 9-10.

Tema ovog završnog rada je korozijska postojanost slojeva aluminijske legure dobivene postupkom aditivne proizvodnje električnim lukom i žicom (WAAM). Rad je podijeljen u dva dijela, prvi teorijski i drugi eksperimentalni. U teorijskom dijelu opisani su postupci aditivne proizvodnje, te uspoređeni međusobno. Opisane su prednosti i nedostaci postupka aditivne proizvodnje električnim lukom i žicom u odnosu na tradicionalne postupke proizvodnje. Navedeni su i opisani najčešći oblici korozije koji se pojavljuju kod aluminija i njegovih legura. Nadalje, opisana je podjela aluminijskih legura prema načinu proizvodnje i objašnjeno njihovo označavanje. Navedena je podjela aluminijskih legura prema glavnom legirnom elementu, te opisan utjecaj tog legirnog elementa na mehanička svojstva i korozijsku otpornost aluminijske legure. Na kraju teorijskog dijela opisan je utjecaj postupka aditivne proizvodnje električnim lukom i žicom na korozijsku otpornost aluminijske legure serije 5XXX. U eksperimentalnom dijelu, opisana je aditivna proizvodnja uzorka (WAAM), izrada manjih uzoraka na kojima će se provesti ispitivanja, njihova naknadna obrada i priprema. Ukupno su ispitana četiri uzorka, tri odvojena strojnom obradom s uzorka proizvedenog aditivno (WAAM), i jedan uzorak od osnovnog materijala, aluminijske legure 5083. Ispitan je kemijski sastav izrađenih uzoraka, te su provedena elektrokemijska ispitivanja. Rezultati su analizirani i uspoređeni. The topic of this thesis is the corrosion resistance of aluminum alloy layers obtained by the process of wire arc additive manufacturing (WAAM). The paper is divided into two parts, the first is theoretical and the second is experimental. The theoretical part describes the processes of additive manufacturing and compares them. The advantages and disadvantages of the wire arc additive manufacturing relation to traditional manufacturing processes are described. The most common forms of corrosion that occur in aluminum and its alloys are listed and described. Furthermore, the division of aluminum alloys according to the method of manufacturing is described and their numeration is explained. The division of aluminum alloys according to their main alloying element is given, and the influence of the main alloying element on the mechanical properties and corrosion resistance of aluminum alloy is described. At the end of the theoretical part, the influence of the wire arc additive manufacturing on the corrosion resistance of aluminum alloy series 5XXX is described. In the experimental part, wire arc additive manufacturing (WAAM) of the sample, production of smaller samples on which tests will be performed, their post-processing and preparation are described. A total of four samples were tested, three separated by machining from a sample manufactured additively (WAAM), and one sample of base material, aluminum alloy 5083. The chemical composition of the samples was tested, and electrochemical tests were performed. The results were analyzed and compared.

Continuous advancements in the electrification of the whole automotive industry rely heavily on the use of lightweight materials. Due to the overall requirements for mass reduction that such rapid development imposes, lightweight materials such as aluminum play a major role in the optimization and development of powertrain components and vehicles while at the same time ensuring the structural integrity of the system. In the introduction of this thesis a short overview of the four most common fatigue assessment methods is given which includes the description of the approaches based on nominal stress, structural hot spot stress, and effective notch stress as well as the crack propagation analysis. In the continuation of the thesis the focus will be on the fatigue assessment of weld seams joining extruded aluminum profiles with the use of modern-day fatigue assessment tools. A closer look will be given into the notch stress-based method behind FEMFAT Weld analysis tool and its benefits for the weld seam fatigue investigations. The fatigue assessment method for welded components proposed by FEMFAT Weld will be validated on an example of welded aluminum profiles from the literature before final experimental investigations begin. In the main focus of the work will be the high cycle fatigue testing of two different weld seams, I-seam butt weld and corner fillet weld, both made of extruded aluminum profiles. Along with the high cycle fatigue testing, additional microscopic measurements of the weld geometry and hardness will be performed. The results of such investigations will be used to conduct a thorough investigation of FEMFAT Weld in order to understand the notch stress methods that are being used and apply them in the desired way. The final results of fatigue assessment with the use of FEMFAT Weld analysis tool will be compared to the results from high cycle fatigue tests and certain conclusion will be drawn. In the end the work from this thesis will represent a detailed overview of FEMFAT Weld assessment tool and clear instructions on how to customize it to specific needs in respect to weld fatigue assessment. Neprestani napredak u elektrifikaciji cijele automobilske industrije uvelike se oslanja na korištenje lakih materijala. Zbog općih zahtjeva i potreba za smanjenjem mase koje nameće takav napredak, laki materijal kao što je aluminij igraju bitnu ulogu u optimizaciji i razvoju komponenti kako pogonskog sklopa tako i cijelog vozila, dok u isto vrijeme moraju osigurati strukturalni integritet cijelog sustava. U uvodu ovog diplomskog rada dan je kratak pregled četiri najčešće metode procjene zamora koji uključuje opis pristupa temeljenih na nominalnom naprezanju, strukturnom „hot spot“ naprezanju i efektivnom zareznom naprezanju, kao i opis analize propagacije pukotine. U nastavku rada fokus će biti na procjeni zamora šavnih zavara koji spajaju ekstrudirane aluminijske profile uz korištenje suvremenih alata za procjenu zamora. Detaljnije će se razmotriti metoda koja stoji iza FEMFAT Weld simulacijskog alata, a temelji se na zareznom naprezanju, kao i njene prednosti u procjeni zamora. Metoda procjene zamora za zavarene komponente koju predlaže FEMFAT Weld bit će provjerena na primjeru zavarenih aluminijskih profila preuzetom iz literature, prije samog početka eksperimentalnih ispitivanja. U glavnom fokusu rada bit će ispitivanje visokocikličkog zamora dvaju različitih šavnih zavara izrađenih od ekstrudiranih aluminijskih profila, sučeonog I-zavara i kutnog zavara. Uz visokocikličko ispitivanje zamora, izvršit će se i dodatna mikroskopska mjerenja geometrije te mjerenje tvrdoće zavara. Rezultati tih istraživanja poslužit će za provedbu temeljitog istraživanja FEMFAT Weld alata kako bi se bolje razumjele metode zareznih naprezanja koje se koriste kako bi ih se moglo primijeniti na željeni način. Konačni rezultati procjene zamora korištenjem FEMFAT Weld alata usporedit će se s rezultatima ispitivanja visokocikličkog zamora te će se izvući odgovarajući zaključci. Ovaj diplomski rad na kraju će predstavljati detaljan pregled FEMFAT Weld simulacijskog alata i jasne upute kako ga prilagoditi specifičnim potrebama u pogledu procjene zamora zavarenih spojeva.

Visokotlačno litje aluminija je avtomatiziran postopek litja ulitkov, za katerega so značilni kratki cikli in velika produktivnost, saj je postopek namenjen velikoserijski proizvodnji. Pri visokotlačnem litju se lahko zaradi velikih obremenitev na orodju pojavijo razpoke. V našem primeru je prišlo do pokanje stabilne gravurne plošče, zato smo se odločili izvesti mehansko analizo stabilne polovice orodja. Mehanske analize smo se lotili v programskem okolju Abaqus, ki temelji na metodi končnih elementov. Na podlagi rezultatov analize smo ugotovili, da je iz vidika normalnih napetosti orodje najbolj obremenjeno v smeri delovanja zapiralne silne in tlaka tretje faze na območju, kjer orodje ni podprto. Objektivnost rezultatov bi lahko izboljšali, če bi upoštevali še vplive temperature. Aluminum high pressure die casting is an automatic process with short casting cycles and high productivity therefore it is used in mass production. Casting tool can crack due to high loads in the high pressure die casting process. In our case the cracking appeared on the stable fixed die so therefore we decided to do a mechanical analysis of the stable half of the casting tool. We preformed the analysis in the program called Abaqus which is based on finite element method. By the results we found out that in terms of normal stress the tool is most burdened in the derection of the claming force and the third phase pressure in the area where the tool is not supported. The obtained results could be improved if the effects of temperature were taken into account.

U radu su detaljno opisani postupci ispitivanja i uporabe neželjeznih legura u području brodogradnje s naglaskom na bakar, bakrene legure, aluminij i aluminijeve legure. U radu je sve sukladno Pravilima za klasifikaciju brodova Hrvatskog registra brodova. Za gnječene i lijevane materijale definirani su zahtjevi: kemijskog sastava, mikrostrukture, stanja površine, dimenzijskih i geometrijskih tolerancija, obradivosti, toplinske obradivosti, raspoloživih mehaničkih svojstava i postojanosti na koroziju. Opisan je postupak klasifikacije propelera od lijevanih bakrenih legura, također su opisani spojevi aluminija i čelika. Zadnje poglavlje bavi se općenitim mehaničkim ispitivanjima za većinu materijala, tako i za neželjezne legure u brodogradnji. Postupci klasifikacije i ispitivanja zahtijevaju profesionalnu opremu, stručno osoblje i nadležnu inspekciju, kako bi u konačnici dobili kvalitetan proizvod i odobrenje od strane Registra. This paper describes in detail the procedures for testing and use of non-ferrous alloys in the field of shipbuilding with an emphasis on copper, copper alloys, aluminum and aluminum alloys. Everything in the paper is in accordance with the Rules for the Classification of Ships of the Croatian Register of Shipping. For wrought and cast materials, the defined requirements: chemical composition, microstructure, surface condition, dimensional and geometric tolerances, formability, heat treatment, possible mechanical properties and corrosion resistance. The procedure for classification of cast copper propellers is described, aluminum and steel joints are also described. The last chapter deals with general mechanical tests for most materials, as well as for non-ferrous alloys in shipbuilding. Classification and testing procedures require professional equipment, professional workers and competent inspection, in order to ultimately obtain a quality product and approval from the Registry.

U ovom radu obrađena je tema određivanja zasjeka i ispitivanja točnosti osi CNC plazma rezača kod izrezivanja pločevina konstrukcijskog čelika, aluminija i nehrđajućeg čelika debljina 2, 4 i 6 mm. U uvodnom dijelu objašnjena je plazma kao agregatno stanje i tehnologija plazma izrezivanja. Opisani su njeni napretci i razvoj kroz povijest, područja primjene i različite varijante plazma izrezivanja koje su korištene nekoć i koje se primjenjuju i danas. Potom je objašnjen utjecaj različitih parametara koji određuju način provođenja izrezivanja i analizirani su utjecaji različitih primarnih plinova koji se koriste za formiranje plazmenog mlaza i sekundarnih plinova koji štite formirani plazmeni mlaz. U eksperimentalnom dijelu rada je opisano poduzeće u kojemu se nalazi CNC plazma stroj na kojem se provodio eksperiment, zatim su navedeni materijali koji se izrezuju i njihova svojstva, te parametri koji su korišteni za izrezivanje. Nakon opisivanja materijala, dan je detaljan plan pokusa kreiran u programskom paketu Design – Expert po kojem su se provodila izrezivanja ispitnih uzoraka. Po završetku rezanja, svi ispitni uzorci su izmjereni, te su podaci o odstupanjima njihovih dimenzija po x i y osi i odstupanja promjera provrta tablično prikazani i analizirani programskim paketom Design – Expert. Provedena je statistička analiza izmjerenih podataka da bi se na temelju odstupanja dimenzija ispitnih uzoraka utvrdile optimalne vrijednosti zasjeka i jednadžbe koje opisuju dimenzijska odstupanja za svaki materijal i debljinu. Uz iznose zasjeka, analizom je dobiven i uvid u točnost x i y osi stroja. This paper processes the topic of determining the kerf value and axis accuracy of a CNC plasma cutter for the cutting of 2, 4 and 6 mm thick plates of construction steel, aluminum and stainless steel. Introductory part explains plasma as a physical state and the technology of plasma cutting. Its development throughout history, fields of application and different variants of plasma cutting which were used in the past, and which are still being used today, were described. Influence of different parameters which determine how the process will be implemented is explained, along with how do the different gases, which are used to form the plasma jet, and secondary gases, which protect the formed plasma jet, influence the process. Experimental part of the paper describes the firm which houses the CNC plasma cutting machine on which the experiment was performed, afterwards, the materials which are being cut are listed along with their properties and parameters used for the cutting process. After the materials were listed, a detailed plan of the experiment by which the cutting will be performed, created in the Design – Expert software, was given. Upon completition of the cutting, all test samples were measured, and the data regarding their dimensional deviations on x and y axis and hole diameter deviations was tabularly shown and analyzed with the Design – Expert software. Statistical analysis of the measured data was made so that the optimal kerf values and the equations which describe dimensional deviations for each material and thickness could be made, based on the dimensional deviation of the test samples. Along with the kerf values, analysis has also given insight in the accuracy of the x and y axis of the machine.

U teorijskom dijelu rada opisana je proizvodnja, karakteristike i problematika zavarljivosti aluminijskih legura s posebnim osvrtom na primjenu aluminijskih legura u brodogradnji. Detaljno je opisan MIG postupak zavarivanja, a ukratko su objašnjeni ostali postupci zavarivanja aluminijskih legura, poput TIG-a, elektrolučnog plazma postupka, laserskog i zavarivanja trenjem. U posljednjem dijelu teorijskog rada dan je pregled pripreme spojeva za zavarivanje aluminijskih legura prema normi HRN EN ISO 9692-3. U eksperimentalnom dijelu rada odabrana je tehnologija zavarivanja aluminijske legure 6082. Strojnom obradom sukladno normi HRN EN ISO 9692-3 pripremljene su dvije ploče. Provedeno je sučeono zavarivanje radnih komanda impulsnim MIG postupkom. Naposlijetku su provedena nerazorna ispitivanja penetrantima i ispitivanje savijanjem te je izvršena makroskopska i mikroskopska analiza. Na temelju dobivenih rezultata eksperimentalnog rada donesen je zaključak. The theoretical part of this thesis describes the production, characteristics and weldability problems of aluminum alloys with special emphasis on the application of aluminum alloys in shipbuilding. The thesis also contains a detail description of MIG welding process, and a brief explanation of other welding processes used for aluminum alloys, such as TIG, the arc plasma welding, laser and friction stir welding. The final section gives an overview of recommended types of joint preparation for welding of aluminum alloys according to HRN EN ISO 9692-3. In the experimental part the suitable welding technology has been chosen for welding aluminum alloy 6082. In accordance with the HRN EN ISO 9692-3 standard two plates were machined. Butt welding was done using MIG pulse technology. Welds were tested using non-destructive dye penetrant method and bend test, furthermore the macroscopic and microscopic analysis was also done. Based on the results of experimental work the conclusion was made.

U ovom završnom radu obrađuje se tema procesa izrade radioničke dokumentacije aluminijskog radnog broda, odnosno „Alumenjaka“ Salona Var MARAL 590VRT. Kroz završni rad upoznaje se s osnovnim svojstvima aluminija te usporedbom aluminijske slitine i stakloplastike kao najčešćeg kompozitnog materijala za izgradnju manjih do srednjih brodova. Prikazuje se i proces izrade samog aluminijskog broda te zaključak prednosti aluminijskih naspram brodova izrađenih od stakloplastike. Također, kroz završni rad će se prikazati kompletan proces izrade radioničke dokumentacije broda popraćen fazom 3D modeliranja u računalnom programu SolidWorks, tehnička dokumentacija u obliku radioničkih 2D nacrta u računalnom programu AutoCAD te će se prikazati opis procesa odabira, obrade materijala i zavarivanja komponenata aluminijskog broda. Na kraju će još biti prikazana i kompletna dokumentacija registriranja broda u Hrvatski registar brodova., This final paper deals with the topic of the process of making workshop documentation for an aluminum work boat, or "Alumenjak" Salon Var MARAL 590VRT. The final paper introduces the basic properties of aluminum, a comparison of aluminum and fiberglass as the most common composite material for the construction of small to medium-sized ships, the process of making the aluminum ship and the conclusion of the advantages of aluminum ships. Also, the final paper will show the complete process of workshop documentation of the ship accompanied by a phase of 3D modeling in the computer program SolidWorks, technical documentation in the form of workshop 2D drawings in the computer program AutoCAD and will describe the process of selection, processing and welding of aluminum parts. At the end, the complete documentation of ship registration in the Croatian Register of Shipping will be presented.

Zaključna naloga obravnava vpliv poroznosti na življenjsko dobo delov iz aluminija. V nalogi kot material, ki ga preučujemo, uporabimo AlSi7Cu0.5Mg-T6. V prvem delu naloge pregledamo Murakami in El Haddad model določitev trajne dinamične trdnosti, ki ju uporabimo v numerični analizi. Nato pregledamo rezultate fizičnega Wöhlerjevega testa. V drugem delu naloge izvedemo simulacijo preizkusa dinamične trdnosti z uporabo lokalnih materialnih lastnosti in preizkušancu določimo Wöhlerjevo krivuljo. Ugotoviti želimo vpliv lokalnih materialnih lastnosti in primerjati ustreznost modela določitve trajne dinamične trdnosti. In this thesis, the influence of the porosity on the fatigue life of aluminum parts is analyzed. AlSi7Cu0.5Mg-T6 is used as the studying material in the paper. In the first part, the Murakami and El Haddad model are reviewed. Then, the results of the physical Wöhler test are examined. In the second part of the task, a simulation of fatigue life using local material properties is performed and the Wöhler curve is determined from it. The influence of local material properties is determined and the suitability of the models for determining fatigue life is analyzed.

Skladiščenje je zelo pomembno področje pri poslovanju podjetja. V težnji k vedno večji produktivnosti se velikokrat osredotočamo samo na proizvodni del, medtem ko ne upoštevamo dovolj logističnih procesov, ki so prav tako pomembni za nemoten pretok izdelkov in surovin. Podjetje Impol se je zaradi prostorske stiske odločilo za uvedbo avtomatskega konzolnega skladišča za kolobarje aluminijaste folije. S tem se prostorna kapaciteta skladišča poveča na enaki kvadraturi. Pri diplomskem delu smo se osredotočili na izbiro primernega konzolnega skladišča za odlaganje izrazito težkih kolutov aluminijaste folije. Nosilci konzolnega skladišča so bili trdnostno preračunani na upogib, preverila se je tudi ustreznost zvarov. Prav tako je bila izračunana pretočna zmogljivost avtomatskega konzolnega skladišča za kolobarje aluminijaste folije. Warehousing is a very important area in a company´s business. In tendency to increase productivity, we often only focus on the production part, while not considering enough logistics processes that are also important for a smooth flow of products and raw materials. Due to lack of space, Impol d.o.o. decided to implement an automatic console warehouse for aluminium foil coils. This increases the storage capacity at the same square footage. In this thesis we focus on the selection of a suitable console warehouse for the storage of extremely heavy aluminium foil coils. The beams of a console warehouse were calculated on bending strength and the appropriateness of welds was also checked. We also calculated the throughput capacity of the automatic console warehouse for aluminium foil coils.

Tema ovog diplomskog rada je primjena aditivne proizvodnje električnim lukom i žicom u svrhu izrade aluminijskih cijevi pomoću CMT postupka. U teorijskom dijelu objašnjen je pojam aditivne proizvodnje zajedno s principom izrade i karakteristikama. Nadalje, detaljno je objašnjena tehnologija aditivne proizvodnje električnim lukom i žicom s naglaskom na primjenu aluminija i postupke zavarivanja aluminija. Jedan od postupaka zavarivanja aluminija je CMT, modificirana verzija MIG/MAG postupka zavarivanja. Uz detaljan opis principa prijenosa metala u električnom luku, navedene su karakteristike postupka i navedeni osnovni modeli. Na kraju dani su primjeri primjene CMT postupka u WAAM tehnologiji te objašnjeni rezultati ispitivanja. U eksperimentalnom dijelu izrađene su cijevi od dvije aluminijske legure WAAM tehnologijom koristeći CMT postupak. Provedena su ispitivanja mehaničkih svojstava i mikrostrukture, a na kraju je ocijenjena primjenjivost CMT postupka u WAAM tehnologiji i dan zaključak. Topic of this diploma thesis is application of wire and arc additive manufacturing technology used for purposes of manufacturing aluminum pipes with CMT welding process. In theoretical part concept of additive manufacturing is explained along with the manufacturing principle and characteristics. Furthermore, the technology of arc and wire additive manufacturing is explained in detail, with emphasis on aluminum welding processes. One of the aluminum welding processes is CMT, a modified version of MIG/MAG welding process. With a detailed description of the principle of metal transfer in an arc, the process characteristics and the basic models are given. Finally, example of the application of CMT procedure in WAAM technology is explained along with test results. In the experimental part, two aluminum alloy tubes were manufactured using WAAM technology and CMT process. Mechanical properties and microstructure were tested, and in the end applicability of the CMT process in WAAM was evaluated and conclusion was given.

Cilj diplomske naloge je bil izboljšati kvaliteto ulitka s pomočjo računalniških simulacij ter analizirati rezultate vsake izvedene simulacije. Osredotočili smo se predvsem na nastanek poroznosti in zračnih mehurjev med tlačnim ciklom. Simulacije litja smo izvajali s programskim paketom MagmaSoft. Najprej smo opisali proces tlačnega litja in najbolj pogoste napake, ki nastajajo, in delovanje programa MagmaSoft. Nadaljevali smo z analizo in simulacijo ulitka z obstoječimi livnimi parametri, ki so mu sledile simulacije s spremenjenimi livnimi parametri, ki so izboljšali kvaliteto ulitka in so z vidika simulacij ustrezali zahtevam kupca. The objective of the thesis was to improve the quality of casting with the help of computer simulations and to analyze the result of each simulation. The focus was on the formation of porosity and air bubbles during the press cycle. Casting simulations were performed with MagmaSoft software. First, we described the process of high pressure die casting and the most common errors that occur and functions of MagmaSoft software. We continued with the simulation and the analysis of the casting with the existing casting parameters followed by simulations with modified casting parameters which improved the quality of the casting and in terms of simulations, the customer requirements were met.

Tema ovog diplomskog rada je korozijska postojanost aluminijske legure dobivene postupkom aditivne proizvodnje električnim lukom i žicom (WAAM). Rad je podijeljen u dva dijela, prvi teoretski i drugi eksperimentalni. U teorijskom dijelu opisan je postupak proizvodnje aluminijskih legura, njihova podjela prema različitim kriterijima, kao i mehanička svojstva, korozijska postojanost s posebnim naglaskom na seriju 5xxx koja je kasnije ispitivana u eksperimentalnom dijelu. Navedeni su i opisani najčešći postupci zavarivanja aluminija, njihove karakteristike, ograničenja te zavarljivost aluminija. Prikazane su značajke aditivne proizvodnje, njihove prednosti, razvoj te je detaljnije opisana WAAM tehnologija s aluminijskim legurama. Nadalje, opisana je zasebno korozijska postojanost zavarenih spojeva aluminijskih legura, s najčešćim pojavnim oblicima korozije. U eksperimentalnom dijelu, opisana je izrada uzoraka, njihova naknadna obrada, prikazani su parametri pri izradi i dodatni materijal. Izrađena su četiri uzorka, od dvije legure s pomoću dva postupka zavarivanja. Ispitan je kemijski sastav izrađenih uzoraka te provedena makro i mikro analiza površina. Provedena su elektrokemijska ispitivanja, ispitivanje korozijske postojanosti uzoraka u slanoj komori te su analizirani i uspoređeni rezultati. The theme of this thesis is the corrosion resistance of aluminum alloy obtained by the process of wire and arc additive manufacturing (WAAM). This study is divided into two parts, the first is theoretical and the second is experimental. The theoretical part describes the process of making aluminum alloys, classification of alloys according to different criteria, their mechanical stability, corrosion resistance with special emphasis on the 5xxx series, which was later tested in the experimental part. The methods of aluminum welding, their characteristics, limitations and weldability are also described. The features of additive production, their advantages, the development, and described WAAM technology with aluminum alloys in details is presented. A corrosion resistance of aluminum alloys welded compounds and the most common forms of corrosion are described separately in addition. Experimental part is describing pattern making with their post-processing. The parameters of the fabrication and additional material as well are presented. Four samples were made of two alloys using two welding processes. The chemical composition of the fabricated samples was examined and macro and micro surface analyses was performed. Electrochemical corrosion tests and salt spray chamber test were carried out and the results were analysed and compared.

Veličina i oblik kristalnog zrna u mikrostrukturi materijala uvelike utječu na mehanička svojstva. U ovom radu se pomoću brzine ultrazvučnog impulsa pokušava utvrditi usmjerenost kristalnog zrna u uzorku valjanog aluminija. Objašnjen je postupak mjerenja brzine ultrazvučnog impulsa sukladno normi, a mjerenje brzine izvedeno je u smjeru hladnog oblikovanja te okomito na smjer oblikovanja. Size and shape of crystal grain in microstructure of material are largely influencing mechanical properties. Aim of this undergraduate thesis is to examine differences in speed of ultrasound, in different orientations of deformed grains in a cold rolled sample of aluminum. Process of measuring ultrasound speed is explained, and two measuring directions were used, one along direction of rolling and another perpendicular to direction of rolling.

Učinkovitost laserske ablacije je pomemben parameter pri graviranju. Ta je v našem primeru definirana kot razmerje med teoretično energijo, ki je potrebna za odstranitev materiala, in energijo, ki smo jo dovedli v obliki svetlobe obdelovalnega laserja. Uporabili smo nanosekundni (12˗240 ns) Yb vlakenski vir z valovno dolžino 1060 nm. Obravnavana materiala na preizkusih sta bila v našem primeru nerjavno jeklo in aluminij. Z uporabo različnih kombinacij obdelovalnih parametrov, kot so frekvenca ter časovni potek moči, vršna in povprečna moč laserskih bliskov, smo dobili različne globine ablacije materiala. Iz dobljenih vrednosti smo lahko izračunali spreminjanje učinkovitosti laserske ablacije in izvedli analizo. Tako smo ugotovili, da se učinkovitost spreminja z različnimi pogoji in se posledično osredotočili na optimalne parametre, kjer je bila učinkovitost največja. Učinkovitost smo še dodatno povečali z optimizacijo dodatnih parametrov, kot so: hitrost potovanja laserskega snopa po površini, število prehodov, razmik vzporednih poti potovanja laserskega snopa ter s spremembo strategije graviranja. Efficiency of laser ablation is a very important parameter in engraving. In our case it is defined as the ratio between the energy that is theoretically needed for vaporizing a volume of material and the energy of the light radiated by the excitation laser. We used a nanosecond (12-240 ns) Yb fiber laser with a wavelength of 1060 nm. The used materials in our experiment were stainless steel and aluminium. With the use of different parameter combinations like frequency, pulse shape, peak and average power we obtained different material ablation depths. From the acquired data we calculated and analyzed the laser ablation efficiency of the engraving process. We then examined out how the efficiency changes with different conditions and focused on the optimum parameters, that give us the best results. The efficiency we then further increased with optimization of additional parameters, such as scanning speed, number of scans, spacing of scanning lines and scanning strategies.

Aluminij je metal koji je nakon kisika i silicija najrasprostranjeniji element u Zemljinoj kori s udjelom od 8%. Na izložbi u Parizu 1855. godine prvi put je predstavljen u elementarnom stanju. Aluminij je srebrno-bijeli metal koji pripada skupini lakih metala i jedan je od najprimjenjivijih materijala. U Zemljinoj kori ne postoji u elementarnom stanju, nego se dobiva elektrolizom iz aluminijevog oksida (glinice) Al2O3. Karakteriziraju ga mala gustoća, nisko talište i jako dobra provodljivost električne i toplinske energije. [10] Budući da je aluminij izuzetno mekan i krhak, u industriji se uglavnom koriste njegove legure. Najčešći legirni elementi aluminija su magnezij, mangan, silicij, bakar i cink. U nastavku će kroz poglavlja biti detaljnije objašnjena svojstva i primjena Al i Al legura, naročito Al legure EN AW 5083 H111. Detaljno će se razraditi svi postupci elektrolučnog zavarivanja koji su primjenjivi za zavarivanje Al i Al legura te način pripreme spoja i moguće pogreške. U eksperimentalnom dijelu rada prikazani su i analizirani rezultati ispitivanja mehaničkih svojstava sučeonog spoja limova aluminijeve legure EN AW 5083 H111 prema zahtjevima norme HRN EN ISO 15614-2:2007. Aluminum is a metal that, after oxygen and silicon, is the most abundant element in the Earth's crust with an 8% share. At the exhibition in Paris in 1855 it was presented for the first time in elementary shape. Aluminum is a silver-white metal that belongs to a group of light metals and is one of the most applicable materials.Aluminum does not exist in elementary shape in Earth's crust so it is obtained by electrolysis of aluminum oxide (alumina) Al2O3. It is characterized by low density, low melting point and a very good conductivity of electricity and heat. [10] Since aluminum is exceptionally soft and fragile its alloys are mainly used in the industry. The most common alloying elements of aluminum are magnesium, manganese, silicon, copper and zinc. The properties and application of aluminum and aluminum alloys will be explained indetail especially aluminum alloy EN AW 5083 H111. All welding procedures of aluminum and aluminum alloys will be considered in detail. According to the requirements of HRN EN ISO 15614-2:2007, in the experimental part will be presented and analyzed the results of testing mechanical properties of aluminum alloy EN AW 5083 H111.

Aluminijeve zlitine se veliko uporabljajo pri izdelavi raznih izdelkov, pri katerih je pomembno visoko razmerje med trdnostjo in maso. Pri izdelavi kompleksnih izdelkov pogosto naletimo na tehnološke omejitve izdelave, ali pa želimo zmanjšati stroške in količino odpadnega materiala. Zato se v zadnjem času čedalje bolj uveljavljajo aditivne tehnologije, s katerimi rešujemo te izzive. Naloga se osredotoča na izdelavo baze podatkov pri obločnem navarjanju aluminijeve zlitine AlSi5 in optimiziranje postopka. Testi so opravljeni z varilnim robotom in sinergijskim varilnim virom za varjenje MIG/MAG, uporabljen pa je postopek CMT. Predvsem so podrobno preučeni osnovni varilni parametri, ki omogočajo izdelavo kakovostnih navarjenih sten, analizirano pa je tudi odvajanje toplote in razporeditev le-te po varjencu. Izsledki naloge kažejo, da je ob dobrem obvladovanju vnosa toplotne energije mogoče izdelati vizualno kakovostne stene s širino do 4,5 mm in izkoristki materiala nad 80 % , ki jih je po dodatni mehanski obdelavi možno uporabiti za izdelavo tankostenskih izdelkov. Aluminum alloys are used in the manufacturing of many products that require a high strength to weight ratio. In manufacturing of complex products we often reach the technological limits of conventional manufacturing methods or want to reduce costs and the amount of discarded material. To solve these problems, many types of additive technologies are being developed. This paper focuses on creating a database of parameters and optimization of the wire and arc additive manufacturing method for welding of AlSi5 aluminum alloy. The tests are made using a welding robot in combination with a synergic MIG/MAG welding machine and where CMT welding process is used. The emphasis is on the study of core welding parameters that enable quality welded walls to be made. Heat conduction and its distribution across the welded part is also studied. The results of this paper show that through good heat input management, it is possible to produce quality welded walls with widths up to 4,5 mm and material deposition efficiency above 80 % that, after additional machining, can be used for production of thin-walled products.

Specijalni alati za savijanje koriste se od najranijih početaka proizvodnje limenih pozicija. U završnom radu opisan je postupak konstruiranja i izrade specijalnih alata za savijanje, te je ukazano na nužnost njihove upotrebe u današnje doba. Cilj rada je opisati specijalne alate za savijanje, i objasniti drugačiji pristup rješavanja problematike tehnologije savijanja, koja je u mnogo slučajeva ekonomski isplativija i proizvodno prihvatljivija. Rad se temelji na opisu konstrukcije 3 specijalna alata za savijanje. Kod svakog je primjera ukazano na specifičnosti alata koje proizlaze iz vrste materijala krajnjeg proizvoda, pa sve do specifičnih zahtjeva naručitelja alata i proizvoda koji alat formira. Navedeni alati montiraju se na dvije hidraulične preše, na kojima je odrađena kompletna izrada serije limenih pozicija. Special bending tools are used from the earliest beginning of the sheet metal production. In this document is described the procedure for designing and manufacturing special bending tools and the necessity of their use in the present time. The aim of the document is to describe special bending tools and to explain a different approach to solving the problem of bending technology, which is, in many cases, more economically, more profitable and more productive. The document is based on the description of the tree special bending tools. Each example shows the specificity of the tool that arise from the end product material up to the specific requirements of the client. These tools are mounted on two hydraulic presses, which complete the production of a series of sheet metal positions.

Cilj je ovoga rada istražiti kako veličina abrazivnih čestica utječe na intenzitet abrazijskoga trošenja aluminijske legure AA 2024-T351 i tehnički čistoga aluminija. Rad se sastoji od teorijskoga i eksperimentalnoga dijela. U teorijskom dijelu opisano je trošenje, mehanizmi trošenja, abrazijsko trošenje, utjecajni čimbenici pri abrazijskom trošenju i fenomen kritične veličine abrazivnoga zrna. Tijekom eksperimentalnoga istraživanja utvrđeno je da veličina abrazivnih čestica ima veliki utjecaj na intenzitet trošenja ispitivanih materijala. Intenzitet trošenja tehnički čistoga aluminija viši je od Al-legure AA 2024-T351. Kod oba materijala izražena je kritična veličina abrazivnoga zrna. Zbog različite mikrostrukture i svojstava Al-legura ima višu vrijednost kritične veličine abrazivnoga zrna (≈ 125 μm) nego tehnički čisti aluminij (≈ 82 μm). Također je utvrđeno da veličina trošene površine uzoraka utječe na intenzitet trošenja i ne smije se zanemariti pri iskazivanju rezultata. The purpose of this paper is to determine the infuence of abrasive size on wear rate of Al-alloy AA 2024-T351 and technically pure aluminum. The paper is comprised of a theoretical and an experimental part. Wear, wear mechanisms, abrasive wear, influential abrasive wear factors and the phenomenon of critical abrasive size are explained in the theoretical part. During the experimental part it was determined that the abrasive size has a great influence on abrasive wear. Wear rate of technically pure aluminum is higher than the wear rate of Al-alloy AA 2024-T351. Critical particle size is noticeable for both materials. Due to different microstructures and properties, Al-alloy has a higher value of critical abrasive size (≈ 125 μm) than technically pure aluminum (≈ 82 μm). It was also determined that the size of the sample's worn surface affects the wear rate and can not be overlooked when results are reported.

U završnom radu je opisan fizikalni princip elastičnosti materijala, odnosno modul elastičnosti te metode njegovog određivanja. Modul elastičnosti je određen pomoću dvije metode. U svrhu provođenja ispitivanja pripremljeno je 3 vrste uzorka: aluminij, mjed i meki čelik. Ispitivanje je provedeno pomoću kontakntnog ekstenzometra, mehaničkog ekstenzometra i instrumentiranom metodom indentacije. Nakon provedenih ispitivanja provedena je analiza i usporedba rezultata, odnosno utjecaj raspona mjerenja i izabranih parametara ispitivanja te usporedba različitih metoda za određivanje modula elastičnosti. This work describes the physical principle of the materials' elasticity, i.e. Young's modulus of elasticity and its methods of determination. The elastic modulus was determined by two methods. In order to conduct the experiments 3 types of samples were prepared: aluminum, brass and soft steel. The test was performed using a contact extensometer, a mechanical extensometer, and an instrumentized indentation method. After the tests were performed, analysis and comparison of the results, i.e. the influence of the measuring range and selected test parameters and comparison of different methods for determination of the Young's modulus were carried out.

Cilj diplomske naloge je bil doseči zvarni spoj med aluminijem in bakrom z difuzijo. Vzorci cilindrične oblike so se spajali pri različnih temperaturah in časih. Spojeni vzorci so se analizirali s svetlobno in elektronsko vrstično mikroskopijo. Na zvarnem spoju se je izvajala EDS analiza kemijske sestave. Merila se je velikost spoja in velikost prisotnih plasti intermetalnih plasti (CuAl2, CuAl, Cu12Al9 in Cu9Al4). Pri vseh spojih so bile prisotne razpoke, ki so potekale skozi evtektik, razen v nekaterih primerih, kjer so bili prisotni lokalni spoji. Ugotavljal se je vpliv temperature in časa na velikost spoja in velikost intermetalnih plasteh. In this thesis the aim was to create a bond between an aluminum and copper specimen through diffusion bonding. The cylindrical shaped specimens were bonded at various temperatures and times. The interface of the joined couple was analysed by optical microscopy and field emisson scanning electron microscopy. An EDS analyse of the chemical composition was made on the couples interface. The size of the joint and the the present intermetalic layers size were messured (CuAl2, CuAl, Cu12Al9 in Cu9Al4). All the joined samples were cracked through the eutectic layer, except in some cases there were present local joints. The influence of tempreture and time on the size of the joint and the size of the present intermetalic layers were examinate.

Primjena inhibitora korozije vrlo je zastupljena i važna metoda zaštite metalnih konstrukcija od pojave korozije. Njihovoj primjeni prethode mnogobrojna testiranja u laboratorijskom ili realnom okruženju. Budući da broj kreiranih inhibitora raste iz dana u dan, razvoj metoda za ispitivanje njihova mehanizma djelovanja, ekološke prihvatljivosti, zadržavanja na metalnim površinama i same učinkovitosti predstavljaju veliki izazov. U ovom radu prikazan je razvoj metode za ispitivanje zadržavanja parnofaznog inhibitora korozije na aluminiju uz simuliranje kloridima izazvane korozije. Proveden je kontaktni test i nekontaktni testovi u tekućoj i plinovitoj fazi. Razvijana je metoda indikacije zadržavanja inhibitora otopinom bakrovih iona. Uzorci su podvrgnuti mikroskopskim analizama, određivanju gubitka mase aluminijevih pločica i količine otopljenog aluminija u otopinama, te elektrokemijskim mjerenjima potencijala otvorenog kruga i elektrokemijske impedancijske spektroskopije. Provedeni niz testova smatra se početkom razvoja nove metode za ispitivanje zadržavanja parnofaznog inhibitora korozije na metalnoj površini. Perspektiva simuliranja kloridima izazvane korozije u parnoj fazi je u načinu nanošenja klorida na pločice uranjanjem u otopinu natrijeva klorida čija se koncentracija može optimirati. The application of corrosion inhibitors is an important method of protecting metallic structures from corrosion. Their application is preceded by numerous tests in a laboratory or real environment. Since the number of created inhibitors is growing daily, the development of methods for testing their mechanism of action, ecotoxicity, metal surface retention and efficiency is a great challenge. This paper presents the development of a method for testing the retention of the vapor phase corrosion inhibitor on aluminum by simulating chloride-induced corrosion. Contact test and non-contact tests in liquid and vapor phase were performed. The method of indicating the retention of the inhibitor by a solution of copper ions was developing. Samples were submitted to microscopic analysis, measurement of mass loss of aluminum plate and amount of dissolved aluminum in solutions and electrochemical measurements (open circuit potential, electrochemical impedance spectroscopy). The series of tests carried out is considered to be the beginning of the development of a new method for testing the retention of the metallic surface corrosion vapor phase inhibitor. The perspective of simulating chloride-induced corrosion in the vapor phase is in the method of depositing chloride on the metal plates immersion plates in a solution of sodium chloride whose concentration can be optimized.

Tema ovog rada je „MIG zavarivanje Al legura“. Rad je podijeljen u dva dijela, prvi teorijski te drugi eksperimentalni dio. U teoretskom dijelu opisan je znaĉaj i svojstva aluminija i njegovih legura s posebnim osvrtom na primjenu aluminijevih legura u brodogradnji. Ukratko su objašnjeni postupci zavarivanja aluminijevih legura, poput TIG-a, elektroluĉnog plazma postupka, laserskog i friction stir postupka, a detaljnije je opisan MIG postupak zavarivanja. U posljednjem dijelu dan je pregled pripreme spojeva za zavarivanje aluminijevih legura prema normi HRN EN ISO 9692-3. U eksperimentalnom dijelu su zavarena dva suĉeljena spoja aluminijeve legure EN AW 5083, jedan s keramiĉkom podlogom, a drugi koristeći bakrenu podlogu. Aluminijski limovi pripremljeni su sukladno normi HRN EN ISO 9692-3. Za zavarivanja korišten je MIG impulsni postupak zavarivanja. Provedena su nerazorna ispitivanje penetrantima i ispitivanje savijanjem lica i korijena zavara te je izvršena mikroskopska analiza. Na temelju dobivenih rezultata eksperimentalnog rada donesen je zakljuĉak. The theme of this thesis is „GMAW welding of Al alloys“. It is divided into two parts, the first one being theoretical and the second experimental. The theoretical part describes the character and properties of aluminum and its alloys with special emphasis on the application of aluminum alloys in shipbuilding. It briefly explains the welding processes used for aluminum alloys, such as TIG, the arc plasma welding (PAW), laser and friction stir welding, furthermore it contains detail description of GMAW welding process. The final section gives an overview of recommended types of joint preparation for GMAW or GTAW process on aluminum alloys according to HRN EN ISO 9692-3. In the experimental part, sheets made out of aluminum alloy EN AW 5083 were butt welded, one pair of sheets using ceramic backing material and the other using copper backing plate. Aluminum sheets were prepared according to HRN EN ISO 9692-3 standard. Welding was done using GMAW pulse technology. We tested welds using non-destructive dye penetrant method and root and face bend tests, as well making the microscopic analysis. Based on the results of experimental work the conclussion was made.

Zadatak diplomskog rada je dimenzioniranje nosive aluminjiske konstrukcije montažne dvorane prema HRN EN 1999-1-1. Prvo je napravljena statička analiza i dimenzioniranje elemenata po linearnoj teoriji elastičnosti prvog reda u programskom paketu Scia Engineer 16.1. Za odabrane elemente konstrukcije izvršen je proračun spojeva te su napravljeni građevinski nacrti i iskaz materijala., The topic of the thesis concerns design of a prefabricated steel hall according to HRN EN1999-1-1 rules. Static analysis and member design was conducted by using the principles of the first order linear elastic theory within the structural analysis programme Scia Engineer 16.1. Calculation of joints, designs and bill of material was made for chosen elements of structure.

Ovaj diplomski rad obuhvaća elektrokemijsko i gravimetrijsko ispitivanje aluminijeve legure (7075) u Labaratoriju za zaštitu materijala s ciljem određivanja najpovoljnijeg inhibitora u smislu antikorozivne zaštite. U radu su opisani aluminij, korozija i njezini tipovi, ispitivani inhibitori (VpCI 649, natrijev benzoat, eterično ulje ružmarina, med) te vrste provedenih elektrokemijskih ispitivanja. Eksperimentalni dio bavi se istosmjernim elektrokemijskim ispitivanjima kao što su određivanje potencijala otvorenog strujnog kruga, određivanje polarizacijskog otpora, određivanje brzine korozije te metoda cikličke polarizacije. Uz to je i provedena gravimetrijska metoda ispitivanja brzine korozije.

Imajući kao predložak Inter-American Exhibition Centre u Sao Paolu, napravljena su dva modela konstrukcije izrađena od različitih materijala: jedan od aluminija, a drugi od čelika. Dimenzioniranje je izvršeno za obe konstrukcije, a u finalnoj fazi su uspoređeni te su za optimalni model izračunati spojevi i napravljeni nacrti., Taking as a template Inter-American Exhibition Centre located in Sao Paolo, Brazil, two models of construction were made of different materials: one of aluminum and the other of steel. Both were thoroughly calculated and dimensioned, and in the final phase they were compared to each other. In the end calculation of joints and drawings were made for the optimal model.

Tema diplomskega dela je ena najhujših okoljskih nesreč v zgodovini Madžarske in tudi najhujših nesreč v Evropi po Černobilu. Zaradi uničenja stene zadrževalnika je prišlo do izliva rdečega blata v tovarni aluminija v Ajki na Madžarskem. Rdeče blato je stranski produkt pri proizvodnji aluminija in se ga shranjuje v posebnih zadrževalnikih s suho ali mokro tehnologijo shranjevanja. Madžarska je uporabljala slednjo in tako močno zaostajala za ostalim svetom, ki je po večini že prešel na varnejšo suho tehnologijo. Tema je sama po sebi zanimiva že zaradi bližine z našo državo. Nekaj časa po nesreči je bila tudi Slovenija v strahu pred rdečim blatom. Po drugi strani pa je močno odmevala po Evropi in po svetu tako da ni bilo težav z literaturo. Mnogo svetovnih medijev je pokrivalo zgodbo, v pomoč so bile tudi raziskave znanstvenikov po nesreči, prav tako analize ter poročila različnih organizacij za zaščito narave in njim podobni. Ko nesreča enkrat ni bila več tako aktualna, tudi članki na to temo postanejo vse bolj redki, tako da so v tem primeru bili v veliko pomoč Madžarski mediji, ki so tudi leta po nesreči dobro pokrivali dogajanje glede družbene odgovornosti za nesrečo, pomoči prizadetim ljudem in iskanja odgovornih za nesrečo. Omenjeni članki, analize in poročila so predstavljali glavni vir za pisanje diplomske naloge. Ugotovljeno je bilo, da obstaja širok spekter dejavnikov, ki so privedli do nesreče - od korupcije, kršenja okoljskih predpisov, malomarnosti pri gradnji do izjemno deževnega obdobja in prevelike količine blata v zadrževalniku. Rešitev je predstavljala suha tehnologija shranjevanja blata, katero so implementirali po nesreči. Danes obstaja tudi že bolj sofisticiran proces pridobivanja aluminija, pri katerem ostane le minimalna količina odpadnih materialov, a to je zaenkrat še bolj stvar prihodnosti. Diploma thesis is about one of the worst environmental disasters in the history of Hungary and the worst disaster in Europe after Chernobyl breech of red mud in the aluminum factory in Ajka in Hungary due to the destruction of the walls of the reservoir. Red sludge is a byproduct in the production of aluminum and is stored in special reservoirs with either wet or dry storage technology. Hungary was using the latter and was significantly behind the rest of the world, which already switched to safer dry technology. Topic is interesting because of the proximity and some time after the accident, Slovenia was also in fear of the red mud. On the other hand, it strongly echoed in Europe and around the world so there was no problem with the literature. Many of the world media covered the story. Scientific research after the accident, analysis and reports of various environmental organizations and others were also very helpful. After the accident was not so topical, the articles about it became increasingly rare. In this case I had to rely on Hungarian media which was of great help. They had good covering of the accident, developments in company responsible for the disaster and they also wrote about the people affected, how they were getting help and about those responsible. Those articles, analysis and reports were the main source of thesis. It has been found that there is a wide range of factors which led to the accident. Corruption, violations of environmental regulations, negligence in the construction of the pond, exceptional rain period and excessive amount of the sludge in the reservoir. Dry technology represented the solution for the problem and was implemented after the accident. There is already more sophisticated process of extracting aluminum known today. Only the minimum quantity of waste materials remains behind in this process but this is still a thing for the future.

U završnom radu opisan je proces obrade aluminija u pogonu za proizvodnju kontrolnih ruku. Proces je podjeljen u dva sustava. Prvi sustav odnosi se na primarnu preradu aluminija kako bi se dobio komad koji je spreman za daljnju obradu. Drugi dio sustava odnosi se na stroj SW BA W06-22 Njemačke tvrtke “Schwäbische Werkzeugmaschinen” koji se koristi za obradu odljevaka te izradu kontrolnih ruku. Opisan je cijeli proces te su objašnjeni svi dijelovi procesa. Također opisan je i elektromotorni pogon stroja kao i programiranje te CNC upravljanje te je sve popraćeno slikama i skicama kako bi se dobila jasna predodžba o procesu proizvoidnje kao i o gotovom proizvodu The final thesis describes the processing of aluminum in the production facility for the control arms. The process is divided into two systems. The first system relates to the aluminum procesing to form a piece that is ready for further processing. The second part of the system refers to SW BA W06-22 machine from German company “Schwäbische Werkzeugmaschinen” which is used for further processing of aluminum drip-mouldings and production of control arms. The whole process was described and all parts of the process were explained. Also all of the electric motors and CNC programming and control were described and acompanied by pictures and drawings in order to give a clearer view of production process and on the finished product.