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The article presents test results concerning the effect of a cladding method and technological process parameters on geometrical properties and dilution of overlay welds. Test overlay welds were deposited on tubes made of steel 13CrMo4-5. The chemical composition of the filler material used in the deposition process corresponded to that of alloy Inconel 625. The study involved the performance of macro and microscopic metallographic tests of the overlay welds as well as the identification of related dilution. The study also included hardness measurements involving the cross-section of the overlay welds as well as tests of the chemical composition of the overlay weld surface (paying attention to the maximum content of iron in the overlay weld, which should not exceed 5%). Adopted PTA and TOPTIG cladding parameters enabled the satisfaction of the maximum criterion related to the acceptable content of iron in the overlay weld, ensuring the stability of the cladding process and the invariable geometry of the overlay welds around the entire tube circumference.

This work presents the results of the comparison between simulations and experiments of the laser welding of advanced multiphase steel. The numerical simulations of welding with different parameters were carried out using the Sysweld software. The geometry of the weld and structural constituents as well as stress distributions were analyzed. The simulated thermal cycles were incorporated in the JMatPro software to determine the phase transformation kinetics during cooling. The experimental tests were performed to compare the simulations with the real results. According to them, the shape of the weld and its width were symmetrical according to the weld axis. The simulated values were higher compared to the real one at heat inputs higher than 0.048 kJ/mm. The microstructure investigations conducted with scanning electron microscopy showed a good agreement in the fusion zone. Some differences in the microstructure of heat-affected zone and transition zone were identified. According to the phase transformation simulations, the weld should be composed of only martensite. The real microstructure was composed of martensite and some fraction of bainite in the heat affected zone. The more complex microstructure consisting of ferrite, bainite and retained austenite was present in the transition zone. The results of measured and simulated hardness indicated the good agreement with the difference of 17 HV0.1.

The study addresses the results concerning the laser welding of TRIP (TRansformation Induced Plasticity) steel using a beam focused at two spots (also referred to as twin-spot laser welding). The analysis involved the effect of variable welding thermal cycles on the properties and microstructure of welded joints. The tests were performed using a linear energy of 0.048 and 0.060 kJ/mm and the laser beam power distribution of 50%:50%, 60%:40% and 70%:30%. The tests also involved welding performed using a linear energy of 0.150 kJ/mm and the laser beam power distribution of 70%:30%. In addition, the research included observations of the microstructure of the fusion zone, heat affected zone and the transition zone using light microscopy and scanning electron microscopy. The fusion zone was composed of blocky-lath martensite whereas the HAZ (heat-affected zone) was characterised by the lath microstructure containing martensite, bainite and retained austenite. The distribution of twin-spot laser beam power significantly affected the microstructure and hardness profiles of welded joints. The highest hardness (480–505 HV), regardless of welding variants used, was observed in the HAZ.

This work is concerned with comparative tests involving single-spot and twin-spot laser welding of thermomechanically rolled TRIP steel. The welding tests were carried out using keyhole welding and a solid state laser. In the case of twin-spot laser beam welding, the power distribution of beams was 50%:50%. The changes in macro- and microstructures were investigated using light and scanning electron microscopy. Three main zones subjected to the tests included the fusion zone, the heat affected zone and the intercritical heat affected zone (transition zone between the base material and the HAZ). Special attention was paid to the effect of various thermal cycles on the microstructure of each zone and on martensite morphology. The tests involved hardness measurements carried out in order to investigate the effect of different microstructures on mechanical properties of welds.

The article presents results related to the bifocal laser welding of overlap joints made of HSLA and DP high-strength steels. The joints were made using a disk laser and a head enabling the 50-50% distribution of laser power. The effects of the laser welding rates and the distance between laser spots on morphological features and hardness profiles were analyzed. It was established that the positioning of beams at angles of 0° or 90° determined the hardness of the individual zones of the joints, without causing significant differences in microstructures of the steels. Microstructural features were inspected using scanning electron microscopy. Both steels revealed primarily martensitic-bainitic microstructures in the fusion zone and in the heat-affected zone. Mixed multiphase microstructures were revealed in the inter-critical heat-affected zone of the joint. The research involved the determination of parameters making it possible to reduce the hardness of joints and prevent the formation of the soft zone in the dual-phase steel.

The article presents the results of the study of the significance of influence of positioning deposited beads towards direction of abrasive movement, to resistance on grind wear platesHARDPLATE 100S’ abrasive wear. The study on relevance of influence was conducted by using completely randomized design. The range of study has covered testing the metal-material abrasive wear resistance, macroscopic and microscopic metallographic examination and hardness tests.

The work addresses microstructure–property relationships of hot-rolled complex phase steel sheets subjected to various conditions of dual beam laser welding. The article also contains a comparison between single-spot and twin-spot laser welding. Test-related joints were made using a Yb:YAG disc laser having a maximum power of 12 kW and a welding head enabling the focusing of a laser beam on two spots. The tests involved investigating the effect of power distribution on the macrostructure, microstructure and mechanical properties of joints. Microscopic investigations revealed the stabilisation of some fraction of retained austenite in the intercritical heat affected zone (ICHAZ) of joints. The application of the second beam resulted in tempering-like effects in the martensite of the fusion zone and in the HAZ, favourably reducing the hardness of the joint. The use of bifocal welding enabled the obtainment of a 10% hardness reduction in the fusion zone as against single-spot laser beam welding.

The work addresses modified methods of twin-spot laser welding of complex phase steel sheets and investigates the effects of laser beam distribution on the macrostructure, microstructure and hardness. The research-related results were obtained for the beam power distributions of 50%-50%, 60%-40% and 70%-30%. Test joints were made using a Yb:YAG disc laser with a maximum power of 12 kW and a welding head by means of which it was possible to focus a laser beam on two spots. It was found that the change in the laser beam distribution affects geometrical features of the joint. The application of the second beam of lower power enables obtaining tempering-like effects, which finally lead to the beneficial hardness reduction both in the fusion zone and in heat-affected zone. The identification of various microstructural constituents in different zones of the joint was performed using light microscopic micrographs and scanning electron images.

The article presents the possibility of using twin-spot laser welding (i.e. laser welding with focusing a laser beam on two spots) for making overlap joints made of 0.8-1 mm thick HSLA and DP type high strength steel sheets. Joints were made using a Yb:YAG disc laser having a maximum power of 12 kW and a welding head by means of which it was possible to focus a laser beam on two spots, 0.6 mm and 1 mm away. The angle between focuses amounted to 0° or 90°, whereas the power distribution was 50%-50%. With settings as presented above it was possible to obtain high-quality overlap joints. The geometrical parameters of the joints were primarily affected by beams positions (in relation to each other) and, to a lesser degree, by the distance between the focuses. It was possible to obtain a 10% hardness reduction in the fusion zone of the DPHSLA steel joints if the angle between the beams amounted to 90°. The tests also involved microstructural examinations of individual zones of the joints

In the paper, there were shown the results of research on the properties of overlay welds consisted of one and three layers deposited by three types of tubular electrodes of the Fe-Cr-C alloy, Fe-Cr-C-Nb-Mo-W-V alloy and composite consist of tungsten carbide particles in the Fe-Cr-C alloy matrix. The study of hardfacing deposits included: test of met- al-mineral abrasion resistance, metallographic examinations, analysis of chemical compo- sition, and hardness tests. The test of abrasive usage in metal-mineral friction was made according to the procedure A of the ASTM G 65 standard.

The work concerns the studies on non-metallic inclusions occuring in laser-welded Si-Al TRIP steel containing Nb and Ti microadditions. Laser welding tests of 2 mm thick thermomechanically rolled sheets were carried out using keyhole welding and a solid-state laser. The results of laser welding in the air atmosphere for the heat input value of 0.048 kJ/mm are included. The distribution, type and chemical composition of non-metallic inclusions formed in the base metal, heat-affected zone, and fusion zone are analysed in detail. It was found that the base metal contains rare, fine oxysulphides. Their chemical composition was modified by rare earth elements. Numerous oxide inclusions of a various size and a chemical composition occur in the fusion zone. The dependence between a size of particles and their chemical composition was observed. A microstructure of steel was assessed using light microscopy and scanning electron microscopy techniques.

This work presents the results of a microstructural characterization of welds in Nb-microalloyed TRIP steel with silicon partially replaced by aluminum. Tests of laser welding of thermomechanically processed sheet samples were carried out using keyhole welding and a solid-state laser. Welding penetration tests were conducted for heat input values between 0.037 and 0.048 kJ/mm. Identification of different microstructural constituents was carried out using light microscopy and scanning electron microscopy in the fusion zone (FZ), heat-affected zone (HAZ), and base metal. Special focus was put on the effect of cooling conditions on the stabilization of retained austenite in different zones. The intercritical, fine-grained, and coarse-grained regions of the HAZ were identified. It was determined that enriching austenite with carbon in the intercritical HAZ stabilizes this phase at a level close to the base metal, i.e., a 15% volume fraction. Despite a high cooling rate in the FZ and HAZ, interlath retained austenite is also present in these zones. The research involved microhardness measurements and characterizing non-metallic inclusions formed in the fusion zone. A good correlation between microstructures formed in different weld regions and microhardness results was obtained.

The research involved vacuum tests of brazing properties of silver filler metals, containing tin as well as tin and nickel, and used in brazing of chromium X6Cr17 and chromium-nickel X6CrNiTi18-10 stainless steels. The research also involved testing the strength and structural properties of brazed joints made of these steels. The tests were conducted on filler metals (silver brazing alloys) B-Ag68CuSn-730/755 (Ag68Cu28Sn4) and B-Ag65CuSnNi-740/767 (Ag65Cu28Sn5Ni2) and also, for comparative purposes, on the filler metal B-Ag72Cu-780 (Ag 272 according to PN-EN ISO 17672), most commonly applied in the vacuum brazing of high alloyed stainless steels. The brazing properties of the filler metals were tested by determining their wettability by means of the spreadability method. The strength of brazed joints made of the stainless steels was examined in a shear test. Research-related structural tests involved light and electron microscopy with an energy dispersive spectrometer (EDS). The comparative analysis of the properties of the filler metals revealed the positive impact of tin and nickel on the spreadability and wettability of the silver brazing alloys as well as on the quality and the shear strength of brazed joints.

The basic physical and chemical properties of titanium aluminide alloys based on intermetallic phases TiAl (γ) as well as their brazeability have been discussed. The principles of the diffusion brazing process and application conditions have been presented. The shear strength and structures of the joints of TiAl48Cr2Nb2 alloy based on the TiAl (γ) phase diffusion brazed with the use of sandwich type silver filler metal (grade B-Ag72Cu-780 and Ag96Cu alloy as a filler metal), copper (grade B-Cu100-1085) interlayers as well as brazing conditions have been given. The structural tests were conducted using light microscopy, scanning electron microscopy (SEM) and energy-dispersion spectrometer (EDS). The results of the shear strength tests were also presented.

In the era of rising energy prices, including fuels for internal combustion engines, a number of research programmes have been initiated, aimed at reducing the weight of motor vehicles and rail veh...

This article presents the phisicochemical propreties of aluminium brings a lot of difficulties during soldering one of tchem is low melting point. The work also presents results of mechanical and metallographic investigations. Structural examination was performed by means of light microscopy and mechanical properties with the aim of shear strength test. On the basis structural investigation joints made with Zn and Zn with Ti addition indicated possibilities of reinforcement of soldered joint of aluminium

Fast-developing such advanced industries as aviation, automotive and power-generation are increasing demand for new engineering materials which could resists such extreme operation conditions as high operating temperature, considerable stresses or operation in fume-affected environment. Highly desirable properties of such materials should include high hardness and strength, corrosion resistance (also when exposed to aggressive fumes) but also, first of all, low density. However such materials also requirements engineering methods to ensure obtain of good sound joints. Results in growing interest in modern engineering materials characterised by increasingly better operational parameters combined with a necessity to obtain joints of such materials representing good operation properties create important research and technological problems of today. These issues include also titanium joints or joints of titanium alloys based on intermetallic compounds. Brazing is one of the basic and sometimes even the only available welding method used for joining the aforesaid materials in production of various systems, heat exchangers and, in case of titanium alloys based on intermetallic compounds, turbine elements and space shuttle plating etc. This article presents the basic physical and chemical properties as well as the brazability of alloys based on intermetallic compounds. The work also describes the principle and mechanisms of diffusion-brazed joint formation as well as reveals the results of metallographic and strength tests involving diffusion-welded joints of TiAl48Cr2Nb2 casting alloy based on TiAl (γ) phase with the use of sandwich-type layers of silver-copper-titanium based filler metal (Ag-63%; Cu-35,5%; Ti-2%). Structural examination was performed by means of light microscopy. Furthermore, the article reveals the results of shear strength tests involving the aforementioned joints. Obtained mechanical test results of TiAl48Cr2Nb2 joints brazed with usage of three/different filler metal alloys ware compared.

Testing of brazing properties of silver fillers of the Ag72Cu28, Ag68Cu28Sn4 and Ag65Cu28Sn5Ni2 type for vacuum brazing of chromium–nickel and chromium stainless steels on the basis of the spreading test are discussed. Mechanical properties of welded joints and results of metallographic and structural examination are presented.

The classification of aluminium alloys on the basis of main alloy elements and usability for heat treatment is presented. The essential problems occurring in welding of aluminium and its alloys are mentioned. The most advanced methods of joining these materials are described. Results of investigations into the possibility of joining of thin walled elements of aluminium alloys by low heat input arc welding methods, plasma arc welding and hybrid laser+MIG welding are also presented.

The paper presents the basic physicochemical properties and brazability of titanium. The work also discusses the principle and mechanisms of the formation of a diffusion-brazed joint and presents results of metallographic and strength-related tests involving diffusion-brazed joints made of technical titanium grade 2 via copper layer grade B-Cu100-1085. The paper also contains results of structural examination conducted by means of light microscopy as well as results of shear strength tests.

The paper deals with the problems of the tram vehicle control according to the criterion of the minimum electric energy consumption. The authors have extended the methodics given in literature and have elaborated the algorithm of the energysaving tram traffic taking into consideration various ride disturbances. During the running within the framework of the city conditions tram ride parameters change frequently. The mathematical models take into account the field-oriented control of traction three-phase squirrel-cage induction motors. Determination of the run algorithm ensuring the minimization of the electric energy use has been realized by application of the optimization procedure.

Praca dotyczy problematyki spawania laserowego stali typu CPW 800 z mikrododatkami Ti i Nb. Próby spawania laserowego blach walcowanych termomechanicznie prowadzono techniką głębokiego przetopienia z wykorzystaniem lasera na ciele stałym. Przeprowadzono próby przy różnej energii liniowej procesu, a następnie wykonano badania metalograficzne makroskopowe i mikroskopowe oraz oceniono twardość materiału rodzimego, strefy wpływu ciepła i spoiny. Określono wpływ energii liniowej spawania na szerokość spoiny. Twardość spoiny wynosi około 400 HV1 niezależnie od energii liniowej spawania, a dominującym składnikiem strukturalnym złącza jest martenzyt niskowęglowy. Przedstawiono wyniki badania wytrzymałości na rozcią- ganie połączeń spawanych.

W artykule przedstawiono zastosowanie termografii aktywnej do badań nieniszczących połączeń zakładkowych blach spawanych laserowo bez pełnego przetopienia. Opisano opracowaną metodologię badań, sposób wytworzenia połączeń próbnych oraz zastosowane stanowisko badawcze. Uzyskane obrazy termograficzne zostały poddane analizie polegającej na wyznaczeniu maksymalnego kontrastu temperaturowego. Ocenę wykonanych połączeń przeprowadzono na podstawie analizy makrostruktury wybranych przekrojów poprzecznych próbek. Na podstawie wyników badań termograficznych stwierdzono, że zaproponowana metoda może być z powodzeniem zastosowana do nieniszczących badań połączeń zakładkowych spawanych laserowo. Active thermography as a new non-destructive testing method of laser welded lap joints Abs􏰤􏰁tract The application of active thermography for non-destructive testing of laser welded lap joints (with partial joint penetration) was presented in this article. The methodology, specimen preparation and applied apparatus were described. Thermal images of the specimens obtained during experiments were analyzed using procedure based on maximum thermal contrast determination. Prepared la- ser welded lap joints were examined using typical macro image analysis of selected cross sections of joints. The obtained experimental results showed that considered method has a great potential to be successfully applied for non-destructive testing of laser welded lap joints.

W artykule dokonano przeglądu wysokowytrzymałych stali AHSS stosowanych w motoryzacji na odpowiedzialne elementy struktury nośnej samochodów. Przeanalizowano zasady projektowania składu chemicznego i mikrostruktury stali wielofazowych typu DP, TRIP i CP, a także właściwości mechaniczne i technologię wytwarzania blach. Scharakteryzowano metody łączenia blach cienkich dla motoryzacji. Szczególną uwagę poświęcono spawalności stali AHSS, wskazując na główne trudności technologiczne występujące podczas zgrzewania oporowego i spawania laserowego. Artykuł uzupełniono wynikami badań własnych spawalności stali CP i TRIP. Weldability of high-strength multiphase AHSS steels Abstract The review of advanced high-strength AHSS steels used in automotive industry for important elements of the body-in-white has been presented in the paper. The principles of the design of chemical composition and microstructure of multiphase DP, TRIP and CP-type steels as well as mechanical properties and manufacturing tech- nology of sheets have been analysed. Joining methods used for automotive steel sheets have been characterized. The special attention has been paid to weldability of AHSS steels with indicating major technological problems occurring during their resistance spot welding and laser welding. The paper contains some authors’ results on weldability of CP and TRIP steels.

W artykule zawarto zestawienie norm jakościowych stosowanych dla połączeń lutowanych twardym lutem. Przedstawiono najczęściej występujące niezgodności lutownicze w połączeniach lutowanych i główne przyczyny ich powstawania. Przeprowadzono przegląd klasycznych metod badań niszczących i nieniszczących oraz określono ich przydatność do badań połączeń lutowanych w zależności od ich konstrukcji. Przedstawiono wyniki badań jakości połączeń lutowanych z wykorzystaniem termografii aktywnej jako nowatorskiej metody badań nieniszczących. Quality inspection of brazed joints Abstract Specification of quality standards using for brazed joints. Imperfection which are most often in brazed joint and reasons for coming into existence. Review of classic of non destructive testing (NDT) and destructive (DT). Usability of nDT and DT to examination of different type of brazed joints. Results of quality examination of brazed joints with the aim of active thermography as a modern non destructive testing method.

Properties and application of alloys based on intermetallic phase titanium, nickel and iron with aluminum. The methods of joining alloys based on this phases. The results of technological researches on brazing of TiAl, Ni3Al, and Fe3Al based alloys, conducted in Institute of Welding in Gliwice. Mechanical and structural properties of brazed joints. in polish Lutowanie twarde stopów na osnowie aluminidków W artykule omówiono właściwości i zastosowanie stopów na osnowie faz międzymetalicznych tytanu, niklu i żelaza z aluminium oraz metody łączenia stopów na osnowie tych faz. Przedstawiono wyniki badań technologicznych nad lutowaniem twardym stopów na osnowie faz TiAl, Ni3Al, i Fe3Al, prowadzonych w Instytucie Spawalnictwa w Gliwicach, a także właściwości mechaniczne i badania strukturalne połączeń lutowanych.

Lutowaniu aluminium towarzyszy wiele problemów wynikających z właściwości fizykochemicznych metalu w szczególności niskiej temperatury topnienia aluminium i trudności z doborem lutu dobrze zwilżającego po- wierzchnię metalu oraz niepowodującego erozji materiału podstawowego. Wykonano badania przydatności do lutowania aluminium stopów Zn-Al, czystego cynku oraz cynku z dodatkiem tytanu jako spoiwa. Przedstawiono wyniki badań mechanicznych i metalograficznych wykonanych połączeń lutowanych. Effect of titanium addition in zinc filler metal on wettability and mechanical properties of aluminum soldered joints Abstract The physicochemical properties of aluminum brings a lot of difficulties during brazing and soldering – especially low melting point of aluminum. There is required selection of filler metal which ensures good wetting and non erosion of base metal. The soldering properties of Zn-Al alloy, pure zinc and zinc with titanium addition was investigated. The mechanical properties as well as the microstructure of the soldered joints were also studied.

W artykule opisano zastosowanie termografii aktywnej do badan nieniszczących polączen lutowanych. Omowiono metodologie badan oraz zastosowane stanowisko badawcze wlasnej konstrukcji. Uzyskane obrazy termograficzne probek zostaly porownane z wynikami badan radiograficznych. na podstawie wynikow stwierdzono, ze zaproponowana metoda badawcza moze byc z powodzeniem zastosowana do nieniszczącej analizy jakości zakladkowych polączen lutowanych. The application of active thermography for non-destructive testing of brazed joints Abstract The application of active thermography for non-destructive testing of brazed lap joints was presented in this article. The methodology and applied self-constructed apparatus were discussed. Thermal images of the specimens obtained during experiments were compared with radiography examination results. On the basis of obtained results, it was summarized that the proposed testing me- thod can be successfully applied for non-destructive quality analysis of brazed lap joints.

W artykule omówiono problematykę lutowności tytanu. Opisano zasadę procesu i mechanizmy powstawania połączeń wykonanych poprzez lutowanie dyfuzyjne. Przestawiono wyniki badań metalograficznych i wytrzymałościowych połączeń tytanu technicznego (grade 2) lutowanego dyfuzyjnie z użyciem przekładek z miedzi (CF032A) i niklu (Ni 99,0) oraz podano parametry lutowania dyfuzyjnego. Badania metalograficzne przeprowadzono przy zastosowaniu mikroskopii świetlnej. Podano wyniki statycznej próby ścinania uzyskanych połączeń lutowanych. Diffusion brazing of titanium with copper and nickel as a filler metals The brazeability problem of titanium and its alloys have been discussed in the paper. The principles of the diffusion brazing process and application conditions have been presented. The structures and mechanical properties of the joints of titanium (grade 2) diffusion brazed with the use of sandwich type copper (grade CF032A) and nickel (Ni 99,0) as a interlayers as well as brazing conditions have been given. The structural tests were conduced using light microscopy. The results of shear strength tests of obtained joints were also presented.