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EN
This paper presents a machine learning and image segmentation based advanced quality assessment technique for thin Refill Friction Stir Spot Welded (RFSSW) joints. In particular, the research focuses on developing a predictive support vector machines (SVM) model. The purpose of this model is to facilitate the selection of RFSSW process parameters in order to increase the shear load capacity of joints. In addition, an improved weld quality assessment algorithm based on optical analysis was developed. The research methodology includes specimen preparation stages, mechanical tests, and algorithmic analysis, culminating in a machine learning model trained on experimental data. The results demonstrate the effectiveness of the model in selecting welding process parameters and assessing weld quality, offering significant improvements compared to standard techniques. This research not only proposes a novel approach to optimizing welding parameters but also facilitates automatic quality assessment, potentially revolutionizing and spreading the application of the RFSSW technique in various industries
EN
The aim of the research was to select a material from which a washer can be made, so that it can be connected to an E355 steel tube by Rotary Friction Welding (RFW). It was decided to choose the steel grade X6CrMo17-1. The numerical model of the RFW process was built using the finite element method (FEM) using the ADINA System software. The numerical model takes into account the friction coefficient with variable values depending on the temperature. Numerical simulations of the process made it possible to determine the temperature fields in the weld cross-section. For the assumed process parameters: rotational speed of 14,000 rpm, friction time of 1.5 s and friction force of 600 N, the peak temperature occurred in the middle of the friction surface at the end of the friction phase and amounted to 1050 C. The results of the temperature analysis are one of the most important parameters for the implementation of subsequent calculations, such as the calculation of structural changes, hardness, residual stresses and deformations.
EN
A mathematical model is presented for investigating the temperature field caused by the rotary friction welding of dissimilar metals. For this purpose, an axisymmetric, nonlinear, boundary value problem of heat conduction is formulated with allowance for the frictional heating of two cylindrical specimens of finite length made of Al 6061 aluminium alloy and 304 stainless steel. The thermo-physical properties of materials change with increasing temperature. It was assumed that the coefficient of friction does not depend on the temperature. The mechanism of heat generation due to friction on the contact surface with the temperature field of samples is considered. The boundary problem of heat conduction was reduced to the set of nonlinear ordinary differential equations at time t relative to the values of temperature T at the finite elements nodes. The numerical solution of the problem was obtained with the inverse 2nd order differentiation method implemented in COMSOL FEM system (finite element method), with time step ∆t=0.1 (s). The influence of various values of friction coefficient is presented.
EN
Thermal phenomena related to plastic deformation can be commonly observed. By simply touching a ruptured or bent sample, it is clear that the temperature has risen at the deformation site. Such observations can be carried out for qualitative or quantitative assessment. This paper serves to qualitatively relate the changes in the structure of the deformed material to the temperature increase observed with an infrared camera.
EN
Present study introduces effect of forge application and elimination on microstructural and mechanical properties of AISI 316 during friction welding. Temperature measurements, microstructure, micro-hardness, tensile test, scanning electron microscopy and X-ray diffraction were evaluated. Maximum temperature recorded was 819°C while forge was applied between 357°C-237°C. Thermo-mechanically affected zone and highly plastically deformed zone were created at the interface at elimination and application of forge respectively. Ultimate tensile strength decreased and ductility increased when forge elimination compared to forge application. Tensile fracture was occurred adjacent to the welding interface for both cases, though, after forge application, ductile fracture mode and cleavage features through the fingerprints were observed in the fracture morphology. Redistribution and concentration of gamma iron in 111 level after forge application and heat treated of AISI 316.
EN
The aim of the study was to implement an integrally configured method of quality control of frictional welding of piston forgings intended for Diesel Man trucks. The use of the method (consisting of the 5W2H method, the Ishikawa diagram and the ABCD - Suzuki method) would contribute to the detection of the causes of non-compliance and consequently to the elimination of non-compliant products. Steel pistons have become the subject of research due to significant problems with maintaining their expected level of quality after the introduced structural and technological changes. The proposed method has helped to identify the root cause of non-compliance. It was: incorrect design of the combustion chamber in terms of diameter and depth. The study shows that it is advisable to use an integrated approach to finding the causes of quality problems on the example of the friction welding process. This was a new solution for the company, as no in-depth analyses of quality problems using a sequence of quality management techniques have been carried out so far.
EN
The paper describes an innovative technology of robotic friction welding of steel studs to the surface of HSS and UHSS sheets and plates of structures, in all welding positions. It specifies basic parameters of the process of friction welding of steel studs to HSS and UHSS sheets and plates. This process ensures a significant increase in the quality and mechanical properties of stud + sheet/plate joints, great ease in controlling welding parameters and monitoring the quality of the welding process, as well as high cost-efficiency and safety of operation. A station for robotic friction stud welding equipped with a real-time monitoring and control system for the quality of welded joints is also described.
8
Content available remote Solid-state welding of ultrafine grained copper rods
EN
The article focuses on the Direct Drive Rotary Friction Welding of ultrafine-grained copper rods, which feature increased mechanical properties and good electrical properties, yet are limited in size. The use of UFG metals is often limited by the too small dimensions of semi-finished elements produced by SPD methods. Therefore, the production of finished machine parts from UFG metals is currently economically unjustified. Dismissal of dimensional limitations can be done by introducing joining to technological processes. The proposed joining method does not lead to a melting of the material in the joining zone or excessive degradation of the UFG microstructure. To obtain the best results, the research used the method of low-energy welding of two kinds of specimens: with a flat or a conical contact surface. In the article, the authors present, by means of metallographic microsections and microhardness measurements, the influence of rotational speed, welding pressure and conical shape contact surface on the quality of the obtained joints. The conducted research made it possible to obtain good quality joints whose microhardness is reduced only by about 10% in comparison with the base material and the tensile strength dropped from only 397–358 MPa.
EN
Friction welding is one of the most economical process of joining solid-state materials. This technique allows to weld similar and dissimilar materials in a very short time. Friction welding of metal with composites gives new possibilities of application, due to the fact that materials have different physical and mechanical properties. In the study, aluminum alloy 44200 was friction welded to Al/Al2O3 composite. In addition, the following inspections were performed: optical microscopy, microhardness measurements and also tensile strength for all joints produced by friction welding. All of the studies were performed to evaluate the quality of connection between the 44200 alloy and the composites on the aluminum alloy matrix reinforced with ceramic phase of Al/Al2O3.
PL
Zgrzewanie tarciowe to jedna z bardziej ekonomicznych metod trwałego łączenia materiałów w stanie stałym. Metoda ta umożliwia wykonywanie złączy zarówno jednoimiennych, jak i różnoimiennych w bardzo krótkim czasie. Zaletą zgrzewania tarciowego jest możliwość uzyskania złączy o wysokiej jakości. Zgrzewanie tarciowe kompozytów z metalami, stwarza nowe możliwości aplikacji, z uwagi na fakt, że oba materiały posiadają różne właściwości fizyczne oraz mechaniczne. W pracy przeprowadzono próby spajania stopu aluminium EN-AC-44200 z kompozytami Al/Al2O3. W opracowaniu przeprowadzono następujące badania złączy stop aluminium-kompozyt uzyskanych metodą zgrzewania tarciowego: mikroskopowe, twardości, mechaniczne (pomiar wytrzymałości na rozciąganie). Wykonane badania miały na celu ocenę jakości połączenia pomiędzy stopem 44200, a kompozytami na osnowie stopu aluminium wzmacnianymi fazą ceramiczną Al/Al2O3.
EN
In order to meet the current requirements of the automotive industry, associated with the creation of a machining center for the production of cylindrical welded and turned components for the construction of solenoid valves, innovative technologies are needed for joining different materials of construction. The article presents the results of the research on the applicability, production of steel electrovalves elements in the AISI303 and 11SMnPb30 grades, an innovative solution consisting in the combination of HSFW high speed friction welding and friction welding using the FSW method. As part of the research, inter alia, a welding station, selection of the shape and dimensions of tools, selection of welding parameters for the HSFW / FSW method, and tests of mechanical properties of the resulting joints were carried out. The obtained results indicate that the obtained connections are characterized by high and reproducible quality.
PL
W celu spełnienia obecnych wymagań branży motoryzacyjnej, związanych ze zbudowaniem centrum obróbczego do wytwarzania cylindrycznych komponentów zgrzewanych i toczonych do budowy elektrozaworów, potrzebne są innowacyjne technologie łączenia różnoimiennych materiałów konstrukcyjnych. W artykule przedstawiono wyniki badań dotyczące możliwości zastosowania, do produkcji elementów elektrozaworów ze stali w gat. AISI303 oraz 11SMnPb30, innowacyjnego rozwiązania polegającego na połączeniu technologii zgrzewania tarciowego wysokoobrotowego HSFW oraz zgrzewania tarciowego metodą FSW. W ramach badań opracowano m.in. stanowisko do zgrzewania, dokonano doboru kształtu i wymiarów narzędzi, doboru parametrów zgrzewania dla metody HSFW/FSW oraz przeprowadzono badania własności mechanicznych powstałych złączy. Uzyskane rezultaty wskazują, że otrzymane połączenia cechują się wysoką i powtarzalną jakością.
11
Content available Friction Weldability of UFG 316L Stainless Steel
EN
The broad range applications of Ultra-Fine Grained metals is substantially limited by the lack of a welding method that allows them to be joined without losing the strong refinement of structure. From this point of view, the solid state welding processes are privileged. Friction welding tests were carried out on UFG 316L stainless steel. A joining process at high temperature activates the recrystallization, therefore the friction welding parameters were selected according to the criterion of the lowest degree of weakness due to recrystallization in the heat affected zone. In order to characterize the structure of basic material and selected areas of the obtained joint, were performed SEM, TEM and metallographic examinations in terms of hardness and range of softening of the material and tensile test. Despite the short time and relatively low welding temperature, results of the test by scanning electron microscopy and transmission electron microscopy confirmed the loss of the primary ultrafine structure in the Heat Affected Zone of welded joint.
PL
W artykule opisano stosowane aktualnie w przemyśle technologie spawania termitowego i zgrzewania oporowego iskrowego szyn trakcji kolejowych dużej prędkości oraz nowoczesne stale niskostopowe bezwęglikowe bainityczne, zapewniające wysokie własności mechaniczne i trybologiczne szyn. W celu znacznego zwiększenia jakości złączy doczołowych szyn i ekonomiczności procesu łączenia zaproponowano dwie innowacyjne technologie łączenia szyn: spawanie laserowe oraz zgrzewanie tarciowe wibracyjne.
EN
The article describes currently used technologies of the thermite welding and resistance flash welding of the butt joints of high-speed rails and modern low-alloy, carbidefree bainitic steels, that ensure high mechanical and tribological properties of rails. In order to significantly increase the quality of the butt joints of rails and the cost-effectiveness of the joining process, two innovative rail joining technologies have been proposed: laser welding and vibration friction welding.
13
Content available remote Zgrzewanie tarciowe ultradrobnoziarnistej stali 316L
PL
W artykule omówiono problematykę zgrzewalności metali o ultradrobnoziarnistej strukturze. Problem omówiono na przykładzie stali 316L o ultradrobnoziarnistej strukturze uzyskanej na drodze obróbki plastycznej hydrostatycznego wyciskania. Złącza uzyskano metodą zgrzewania tarciowego. Parametry zgrzewania dobierano wg kryterium najniższego stopnia rekrystalizacji obszaru złącza. Wykonano badania metalograficzne, scharakteryzowano wybrane obszary złącza zgrzewanego pod względem twardości i zasięgu zmiękczenia materiału. Wykonano próby statycznego rozciągania, porównano wytrzymałość na rozciąganie materiału rodzimego oraz złącza zgrzewanego.
EN
The article discusses the issues of weldability of metals with UFG (ultrafine grained) metals. The problem was discussed on the example of 316L steel with UFG structure obtained by metal forming method of hydrostatic extrusion. The joints were obtained by friction welding. Welding parameters were selected according to the criterion of the lowest degree of recrystallization of the joint area. Metallographic examinations were performed, selected areas of the joint welded in terms of hardness and range of softening of the material. Static tensile tests were carried out, the tensile strength of the parent material and the welded joint were compared.
PL
W artykule opisano aspekty praktyczne zgrzewania tarciowego, ze szczególnym zwróceniem uwagi na proces trymowania – obróbki ubytkowej wypływki bezpośrednio po zgrzewaniu. Na przykładach produkcyjnych wytłumaczono cel trymowania i zaprezentowano jego alternatywy. Analizowano wpływ wybranych parametrów obróbki (prędkość obrotowa, posuw oraz czas) na wybrane właściwości zgrzein tarciowych. Próbki wykonane przy zmiennych parametrach trymowania poddano badaniom wizualnym, analizie metalograficznej (makro- i mikrostruktura) oraz pomiarom twardości. Dodatkowo dla skrajnych wyników przeprowadzono analizę z wykorzystaniem kamery termowizyjnej. Na podstawie przeprowadzonych badań i testów określono wpływ parametrów obróbki na jakość zgrzein tarciowych.
EN
The practical aspects of friction welding were described in this paper including especially flash removal process occuring directly after welding. To explain the purpose of those processes the production examples and thier alternatives have been shown. The analysis has been prepared based on studies by adjusting siqnificant process parameters (rotation speed, feedrate, time) on indicated welds properties. Samples made with variable flash removal parameters were subjected to visual tests, metallographic analysis (macro- and microstructure) and hardness measurements. Additionally a thermal analysis has been prepared for extreme results. Based on described research, the influence of process parameters on the friction welds quality was determined.
EN
Intense research on the metallurgy of iron alloys have recently resulted in the development of technologies enabling the making of high-carbon nanobainitic steels. Because of their chemical composition, the above-named steels belong to hard-to-weld materials. To identify the possibility of welding such steels using arc-based methods and welding in the solid state it was necessary to make test joints and perform related metallographic tests. The test results revealed that it is possible to obtain both fusion and pressure welded joints if the process was performed in the softened state, i.e. before the final heat treatment. Afterwards, joints should be subjected to a heat treatment ensuring the obtainment of a previously assumed microstructure and required hardness distribution in the weld and HAZ.
PL
Intensywne prace badawczo-rozwojowe w zakresie metalurgii stopów żelaza doprowadziły w ostatnim czasie do opracowania technologii wytwarzania wysokowęglowych stali nanobanitycznych. Stale te ze względu na skład chemiczny należą do materiałów trudno spawalnych. W celu określenia możliwości ich spawania metodami łukowymi oraz zgrzewania w stanie stałym, wykonano złącza próbne oraz przeprowadzono badania metalograficzne w ich obszarze. Wyniki badań wykazały możliwość uzyskania złączy spawanych i zgrzewanych pod warunkiem prowadzenia procesów łączenia blach w stanie zmiękczonym, tj. przed finalną obróbką cieplną. Następnie złącza można poddać obróbce cieplnej gwarantującej uzyskanie założonej mikrostruktury i rozkładu twardości w spoinie i w strefie wpływu ciepła.
EN
There are several factors that influence the friction welding (FW) process, i.e. the quality of the welded joint, like the welding time, the contact pressure, the compacting pressure, the friction speed etc. The joining process is additionally complicated if the two different materials are to be welded to each other. The subject of research, presented in this paper, is the welding time of the FW process, since the level of axial and radial plastic deformation of the welded pieces and shortening of the welded part depend mainly on the welding time. The paper first presents some theoretical basics of the FW process and then, in the experimental part, the influence of the process duration is investigated. The two materials that the experimental samples were made of are the high-speed steel and the steel for tempering.
17
Content available remote Wysokowydajne zgrzewanie FSW stopu aluminium przerabianego plastycznie
PL
Proces zgrzewania FSW jest stosunkowo prosty do realizacji w przypadku łączenia elementów wykonanych z takich samych materiałów lub materiałów nieznacznie różniących się własnościami fizycznymi. Zasadniczo, do tego rodzaju konstrukcji wykorzystuje się niewielkie prędkości zgrzewania. W artykule przedstawiono wyniki badań dotyczące wysokowydajnego zgrzewania metodą FSW stopu aluminium przerabianego plastycznie. Uzyskane rezultaty wskazują, że otrzymane połączenia cechują się wysoką jakością i pozbawione są wad oraz niezgodności.
EN
FSW process is relatively simple for realization in case of welding of similar materials or materials which slightly differ in their physical properties. Principally, for these types of application, low welding speeds are used. The article presents research results connected with high speed FSW welding of wrought aluminium alloy. Obtained results show that welds are characterized by high quality without any defects or imperfections.
EN
The process of friction stir welding is a significant advance in the field of research on the Friction welding technique known for several decades. This assembly technique has obvious originality since welding is performed in the solid state, which can help eliminate birth defects related to solidification phase compared to conventional welding. The numerical modeling of this type of process is complex, not only in terms of the variety of physical phenomena which must be considered, but also because of the experimental procedure that must be followed in order to verify and validate numerical predictions. In this work, a finite element model is proposed in order to simulate the crack propagation under monotonic loading in different areas of the weld seam of a specimen CT-50 aluminum alloy 6082-T6. Microhardness tests were performed to characterize the Vickers hardness profile in the vicinity of the weld area. Friction stir welding process leads to a decrease of the static mechanical properties relatively to base material. Detailed examination revealed a hardness decrease in the thermo mechanically affected zone and the nugget zone average hardness was found to be significantly lower than the base alloy hardness. Welded specimens show significantly lower lives than base material.
PL
Praca dotyczy obrotowego tarciowego zgrzewania wolframowego stopu ciężkiego ze stopem aluminium, które zostało przeprowadzone dla wytypowanych kombinacji parametrów procesu zgrzewania. Badania zostały uzupełnione o symulację rozkładu temperatury na powierzchni próbki wykonaną metodą elementów skończonych w programie ADINA.
EN
The work concerns the rotary friction welding of tungsten heavy alloy with aluminum alloy, which has been carried out for the selected combinations of welding process parameters. The study was supplemented with a simulation of the temperature distribution on the surface of the sample made by means of the finite element method in ADINA program.
EN
The results of studies concerning friction welding of Weight Heavy Alloy (WHA) with AlMg3 alloy are presented. The friction welding of density 17.5 Mg/m3 with aluminum alloy showed that it is possible to reach the joints with the strength exceeding the yield strength of wrought AlMg3 alloy. This strength looks to be promising from point of view of condition which have to be fulfilled in case of armor subcaliber ammunition, where WHA rods play the role Kinetic Energy Penetrators and aluminum is used for projectile ballistic cup.
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