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The paper deals with a modeling of laminate plates and with their buckling analysis. To predict the inception of buckling for plates in plane resultant forces must be included. The buckling analysis is made by the help of finite element method in program COSMOS/M. For rectangular laminate plate consisting of 4 layers with symmetric and antisymmetric stacking sequence a buckling analysis is carried out. In the illustrative example there are depicted buckling modes for symmetric laminates [30/-30]s, [45/-45]s, [60/-60]s, [90/-90]s and results of the buckling analysis for the symmetric and antisymmetric laminates.

The peculiarities of the morphology and structure defects of composite material in the Cu-Mo-Zr-Y system produced from commercially pure raw materials using method of electron-beam evaporation/condensation have been studied. The features of deformation and destruction of the composite have been investigated alongside with its mechanical properties and their change under action of structure defects.

The paper analyzes the influence of the impact rate of up to 120 ms-1 with a constant energy on the relative compression of high-grade unalloyed steels, Cu and Zn, and the evaluation of energy consumed during the impact bending test at the impact rate of up to 80 ms-1. Based on the experiments made, relationships for the prediction of the influence of the strain rate within the range of 10-3 – 2.5.103 s-1 on the mechanical properties of high-grade unalloyed steels with the yield point of 210 – 450 MPa and microalloyed steels with the yield point of 300 – 600 MPa are presented.

The Udimet 500 nickel base superalloy blade exposed for 50000 hours in land base gas turbine working conditions faced the structure degradation. Six different heat treatments procedures have been applied (the blades were exposed at 900 °C and 1000 °C for different periods with maximum hold of 2500 hours) to rejuvenate the degraded structure. Metallographic work was performed, generally, aging at both temperatures modify the gamma prime size, morphology and distribution characteristics substantially. The volume fraction of secondary gamma prime decreased with increasing aging time.

The main tendency towards the development of the methods for predicting long-time data on of metallic materials is to derive the correlation relationships, which should be as general as possible. This paper presents the verification of the fact that a sufficiently accurate estimation of the peculiarities of the portions of experimental diagrams and generalization of this information can be of great importance for a considerable progress in the prediction.

Da bi opstao i zadržao prednost izradbe bešavnih cijevi u odnosu na suvremene valjaonice, kod pilger postupka treba povećati produktivnost, smanjiti troškove prerade i posebice poboljšati kakvoću i površinu cijevi. U članku se daje mogućnost modernizacije pilger stana (pogona, kućišta, posmaka cijevnice, itd.).

The annealing temperature within the range of 1223 - 2273 K has been studied for its effect on the grain size, mechanical properties, cold brittleness temperature, and nature of failure of sheets molybdenum alloys TsM-6 and TsM-10. The method of Auger-electron microscopy has been used to study the change of carbon and oxygen content on grain boundaries of the alloy TsM-10 and the change of mechanical properties associated with it as dependent on the annealing temperature.

The paper analyses the material characteristics of deep-drawability of steel sheets with the thickness from 1 to 1,8 mm, the yield point above 330 MPa and the loading rate up to 150 m/min. The analysis resulted in the finding that with the loading rate up to ca 10 m/min the formability characteristics slightly increase and after exceeding this value these characteristics significantly decrease. In practice, the strain rates are below 1 s–1, therefore the material characteristics determined using standard tests can be used to determine the limit states up to the above-mentioned rate.

The paper analyzes the fatigues properties of galvanized microalloyed steel sheets H220LAD and H380LAD. Under flat bending conditions and the symmetrical cycle, the fatigue limit of the H220LAD sheet is σCo = ± 152 MPa and that of the H380LAD sheet is σCo = ±188 MPa, and the fatigue limit to tensile strength ratio is 0,41 and 0,37, respectively. During fatigue tests with an increasing number of cycles or an increasing stress value, the degradation of the zinc coating increases (relief formation, damage of integrity). As a result, local corrosion, but also continuation of fatigue damage after 107 cycles, and hence corrosion fatigue, can take place during operation.

At the first look very simple and for several hundred years used elastic element can be critical part in complex equipment where its failure invokes extraordinary high losses. In the paper is given a treatment for the solution of this problem by experimental methods and resulting proposal for its final solution.

Low carbon steel AISI 10 was subjected to a severe plastic deformation technique called Equal Angular Channel Pressing (ECAP) at different increased temperatures. The steel was subjected to ECAP with channel’s angle j = 90°, at different temperature in range of 150 - 300 °C. The number of passes at each temperature was N = 3. Light, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) of thin foils were used to study the formation of substructure and ultrafine grains in deformed specimens. The size of newly born polygonized grains (subgrains and/or submicrocrystalline grains) is in range of 300 - 500 mm. The formation of such of predominant submicrocrystalline structure resulted in significant increase of yield stress [Re] and tensile strength of the steel [Rm].

The production of Cu-Zr-Y-Mo Finely-Dispersed (FD) microlayer composite materials for electrical contacts by the method of electron-beam evaporation and layer-by-layer condensation from the vapor phase is described and the chemical composition, structure, density, electrical conductivity, hardness, and main mechanical characteristics of the materials in the temperature range from 290 to 1070 K are studied.

The paper analyzes the influence of the loading rate in the interval from 1 to 1000 mm/min on the mechanical properties of drawing steel sheet H260LAD with the gauge of 1 mm, used for the manufacture of automotive parts, under tension and bending conditions. It describes the aspects of material characteristics under tension and bending conditions, while bending tests were made on notched specimens (a modified impact bending test). The paper presents knowledge that using a modified notch toughness test it is possible to achieve the pressability (formability) characteristics corresponding to dynamic strain rates even under the static loading.

Using the solution of a closed problem of the theory of plasticity some analytic expressions were obtained for determination of the strain parameters of zone of deformation in view of the temperature factor.

The influence of technological factors and constructive parameters of the cold pilger rolling mill to the warm conditions of deformation is observed. The dependences of the heat conditions of pilger rolling on deformation mode and preheating temperature are shown. There was a conclusion drawn about the expediency of combination of warming and cooling of the metal for keeping the deformation zone temperature within limit, which corresponds to the minimal intensity of the metal strengthening.

The paper considers dependencies of metal forming characteristics on dimensionless geometrical parameters of flat pocket die design at direct extrusion of aluminium thin-walled solid profiles. The theoretical analysis of plastic metal flow is carried out by means of the 2 -D FEM model. The new method for flat pocket die design is proposed in the paper. The die design example is given for non -symmetrical U-shape profile.

The paper deals with the classification of steel sheets for automotives industry on the basis of strength and structural characteristics. Experimental works were aimed to obtain the best possible strengthening parameters as well as work hardening and solid solution ferrite hardening, which are the result of thermal activation of interstitial carbon atoms during paint-baking of auto body. Hardening process coming from interstitial atoms is realized as two-step process. The first step is BH (bake hardening) effect achieved by interaction of interstitial atoms with dislocations. The Cottrels atmosphere is obtained. The second step of BH effect is to produced the hardening from precipitation of the carbon atoms in e-carbides, or formation of Fe32C4 carbides. WH (work hardening) effect is obtained as dislocation hardening from plastic deformations during sheet deep drawing. Experimental works were aimed at as to achieve such plastic material properties after cold rolling, annealing and skin-pass rolling, which would be able to classify the material ZStE220BH into the drawing categories at the level of DQ – DDQ. As resulting from the experimental results, the optimal treatment conditions for the maximal sum (WH+BH) = 86 MPa are as follows: total cold rolling deformation ecold = 65 %, annealing temperature Tanneal. = 700 °C.

The aim of this paper is to consider the features of structure evolution during severe plastic deformation (SPD) of steels and its influence on mechanical properties. The investigation have been carried out mainly on low carbon steels as well as on austenitic stainless steels after SPD by torsion under high pressure (HPT) and equal channel angular (ECA) pressing. Structure formation dependencies on temperature deformation conditions, strain degree, chemical composition, initial state and pressure are considered. The role of phase transformations for additional grain refinement, namely, martensitic transformation, precipitation of carbide particles during SPD and heating is underlined.

In the last decade, a lot of effort has been paid to optimising the thermomechanical processing of TRIP steels that stands for transformation induced plasticity. The precise characterization of the resulting multiphase microstructure of low alloyed TRIP steels is of great importance for the interpretation and optimisation of their mechanical properties. The results obtained in situ neutron diffraction laboratory experiment concerning the austenite to ferrite transformation in Si-Mn bulk TRIP steel specimens, displaying the transformation induced plasticity (TRIP), are presented. The advancement of ferrite formation during transformation in conditioned austenite is investigated at different transformation temperatures and has been monitored using neutron diffraction method. The relevant information on transformation proceeding is extracted from neutron diffraction spectra. The integrated intensities of austenite and ferrite neutron diffraction profiles developed during the transformation are then assumed as a measure of the phase volume fractions of both phases in dependence on transformation temperature and austenite conditioning. According to the yielding information on ferrite volume fractions from isothermal transformation kinetics data the thermo mechanical processing of bulk specimen was designed in order to support austenite stabilization through bainitic transformation. The volume fractions of retained austenite resulting at alternating transformation conditions were measured by neutron and X-ray diffraction respectively. The stability of retained austenite in bulk specimens during room temperature mechanical testing was characterized by in situ neutron diffraction experiments as well.

The authors studied the characteristics of strength of filtering composite materials reinforced by a two-layer nickel mesh with a coating depending on the cutting-out angle. The anisotropy of the characteristics of strength is shown to be the closest to the Ashkenazy phenomenological strength criterion in the form of a fourth degree polynomial, which describes the ultimate strength vs net cut-out angle limiting curve.

Investigation results indicating the influence of high-density impulse electric current on impact toughness of Charpy specimens manufactured from low carbon steel are presented. It is shown, that impulse electric current treatment causes a considerable growth of impact toughness of the steel, and type of material fracture is changed from brittle mode to ductile mode.

This document is a supplement to the "Book of Abstracts" for the 17th Symposium on Materials and Metallurgy. It includes summaries of various research studies related to materials and metallurgy. The topics covered include the fatigue life of automobile bellows, the feasibility of power flexible cable production, real-time detection of green pellets, design of an automatic opening and closing manipulator for ore crushing ball mill cover, formation of slag inclusions in billets during casting, use of amorphous alloys to strengthen pipe tools, research on heat engineering processes of secondary metallurgy, efficient recovery of cobalt from spent lithium-ion batteries, influence of process parameters on grain structure in vertical continuous casting, finite element analysis of connecting shafts in cold rolling mills, effect of acid-soluble aluminum content on precipitates and magnetic properties of grain-oriented silicon steel, selection and priming of technological solutions for refining manganese-based alloys, oxidative conversion of methane on freshly reduced iron, constitutive model of high temperature plastic deformation of P91 alloy steel, steel filtration using multi-hole ceramic filters with an innovative design, and the constitutive model of high temperature plastic deformation of TC17 titanium alloy for underwater robot metal material. [Extracted from the article]

In Metalurgija 62 (2022) 2, 547-576 published „ Book of Abstracts" (323 Abstracts). Deadline for received of Abstracts was October, 31,2021 y. Many authors have request new deadline by December, 31, 2021 y. Organizing committe have accept new deadline. Now it published supplements of 73 Abstracts. [ABSTRACT FROM AUTHOR]

Sixty years have passed since the foundation and the first publishing of the Metalurgija Journal. This the Jubilee is important for all Authors and Co-authors (by scientist, experts in the field of Metallurgy and other relevant branches, readers) from 40 Countries (all 5 Continent) whose investigation results and ideas have been examined and found on the pages of this Journal. The goal of the Article is give List of 3558 Authors and Co-authors publisched 3008 papers 1962 - 2022 See: Metalurgija 61 (2022) 2,401-546. Thanks for all. [ABSTRACT FROM AUTHOR]

For the interval 1962-2022 y, during the continuos publication last 60 years, in Metalurgija Journal Authors from 40 countries from Mexico to China (all 5 continent ) have publish. The goal of the Article is give List of Papers published in this interval, 199 issues or 238 numbers, 2721 scientifi c and technical, and 287 contributions (total 3008 papers ) of Authors whose investigation results and ideas have been examined and found on the pages of this Journal. Thanks for all. [ABSTRACT FROM AUTHOR]

Sixty years have passed since the foundation and the first publishing of the Metalurgija Journal. On the occasion of this Anniversary, the goal of the Article is give List of Boards and Co-workes which dedicated eff ort have managed to over come many technical and organizational problems by regularity publishing. [ABSTRACT FROM AUTHOR]

The Dep. of Metallurgy in Sisak of the Faculty of Technology Zagreb was founded in 1960 with Ironwork Sisak, Petrol rafinery Sisak and Assembly of the Municipality Sisak as Founders. During 60y (1960-2020) were several organizations transforms, important 1977-1978 y when is Metallurgical Dep./Engineering including in Institutza metalurgiju Sisak, name Metallurgical Faculty. With transform 1990-1991 y Metallurgical Faculty have separate from Institutza metalurgiju Sisak and come into existence as autonomous the organization at University of Zagreb. Till now, have publish many works about history, activities in teaching, scientific and professional works and achievements. In this work published several works of different authors, with original texts from founded 1960 till now 2021. [ABSTRACT FROM AUTHOR]

Sixty years have passed since the foundation and the first publishing of the Metalurgija Journal with Scientifi c, as well as Professional Papers and Contributions from the area of basic, applicable and developing researching in Metallurgy and boundary metallurgy areas. The goal of the Article in Croatian and English language is give whole the description history, organizations of Journal activities and achiewements of Journal from 1962 since 2022 y, with this including List of Boards and Coworkers, were publishing total papers 3 008 ie. 2 721 Scientific and Technical and 287 Contributions, total 3 575 Authors and Co-authors from over 40 Countries. On the occasion of this Anniversary, separately with thanks for Privates, Institutions etc. for dedicated eff ort have managed to overcome many technical, organizational and financial problems encountered over past Years. [ABSTRACT FROM AUTHOR]

This work deals with the development of metalurgy in the world whose beginnings date 7 000 years B.C. On the teritory of today s Croatia metalurgy has been present for 6000 years. Three civilizations have left evidence the Celtic, the Roman and civilization of Vučedol. After the arrival of the Cratis to this teritory, metalurgy developed more intensively in the region of Sisak and Banovina as well as Samobor and Gorski Kotar. Bells and guns were cast in Dubravnik and Zagreb. The industrial production starte din 1853 (Foundry in Rijeka), production of ferroalloys, Šibenik 1900 y, also Dugi Rat 1906 y, and in 1937 the production of aluminium and Al – alloys in Lozovac (continuo by 1905) as with the construction of the blast furnace in Caprag in 1939. In the period after 1945 until 1990, Croatia had several metallurgical companies and acceptable production coke, iron, steel, fero-alloys, electrodes, casting, reinforced concrete steel, seamless and welded tubes, strips, billets, aluminium etc. Total production in Croatia in 1990 was ~ 3 000 000 tons of various metallurgical products (without castings). Per year in 1990 until 2012 plants of over 2 600 000 t of metallurgical per year were torn down or put out of operations. Total metallurgical production in Croatia in was 2011 y 248 910 tons i.e. level 8,3 % (comparison with the production in 1990 y), what is significant of the destruction of Croatia metallurgy for 22 years. The Article give also several press notices to the public information by members of the Croatian Metallurgicall Society and Apprentices in order to sustain and revitalize of the Croatian metalurgy (supplements). [ABSTRACT FROM AUTHOR]

The goal of this article is to give an overview of the foundation and development of Croatian Metallurgical Society (CMS) from the Society of Engineers and Technicians of Steelworks Sisak 1952 – 2012 With monitoring of goals and tasks of CMS, the main activities of the Society are also set out: publishing of the magazine Metalurgija, international symposium „Materials and Metallurgy“, and productive cooperation with an array of institutions in Croatia and abroad but also difficulties in the activities (over 70 institutions from 50th countries). The overview includes also several futile press notices to the public made by the member of the Society of their own initiative, in order to sustain and revitalize the Croatian metallurgy. The Society and the Journal survives on the base of modest financial support by the Ministry of Science and Education and Sport (in 2020 y only for Metalurgija Journal 10 000 EUR and cca 3 000 EUR for activities of Society), of Participation Fees from Symposium and exclusively to volontary work all in Society, without any permanent empoloyees. [ABSTRACT FROM AUTHOR]

The paper considers complex intensification features of spheroidizing annealing of low-carbon steels and possible technological realizations of intensive annealing modes in current lines. The research aims to reveal the intensification nature of the steel’s spheroidizing due to the non-isothermal holding and an internal coolant for the metal heating. That allows a significant reduction of the spheroidizing annealing process while improving the steel product’s technological properties – providing a high dispersion and homogeneity of the structure across the entire plane of its section. The multiprocessor computing system with its mathematical and IT software for modeling the heat treatment modes of metal billets effectively controls the processes. [ABSTRACT FROM AUTHOR]

The beginnings of the world metallurgy date back to the 7000 years B.C. On the territory of today's Croatia, metallurgy has been present for 6000 years. Three civilizations have left the evidence of this: Vucedol, Celtic, and Roman civilization. After the arrival of the Croats, metallurgy has been more intensively present in the Sisak-Banovina and Samobor regions, as well as Gorski Kotar region. Casting of bells (and cannons) was developed in Dubrovnik and Zagreb. The industrial production start date was in 1853 (Foundry in Rijeka), in 1937 (the production of aluminium and Al-alloys in Lozovac) as well as in 1939 with the construction of the blast furnace in Caprag. In the period after 1945, until 1990, Croatia had several metallurgical companies and acceptable production of coke, iron, steel, ferroalloys, electrodes, casting, reinforced concrete steel, seamless and welded tubes, strips, billets, aluminium, etc. In 1990, total production of various metallurgical products in Croatia was 2.670.000 tons of which up to 2.000.000 t/y came from Steelworks Sisak. From 1990 to 2012, over 2.600,00 t/g of metallurgical products were demolished or discontinued, which represented the collapse of Croatian metallurgy. The paper cites more important publications on the Steelworks Sisak, which was a long-standing carrier of metallurgical production in Croatia. There is also a review of the last published Proceedings of the Sisak Ironworks (2019). [ABSTRACT FROM AUTHOR]

The goal of this the Article is to give an overview of the foundation, development and achievements of Croatian Metallurgical Society (CMS) from Society of Engineers and Technicians of Steelwork Sisak (SETSS) 1952 - 2017 (65 years) With monitoring of goals and tasks of CMS, the main activities of the Society are also set out: First, history of the metallurgy on the teritory of today Croatia in the therm 6.000 y till today, with many Articles, Studies etc. In this way, Croatia was ranged between Countries where metallurgy as important technical bransh, has a written document on this history. Second, publishing of the Metalurgija Journal, International Symposiums „Materials and Metallurgy" (was 12 with 5.013 Lectures), and productive cooperation with an array Institutions in Croatia and abroad(over 70). [ABSTRACT FROM AUTHOR]