The aim of this work is to study joining Al 2024-T3 alloy plates with different welding procedures. Aluminum alloy AA 2024-T351 is especially used in the aerospace industry. Aluminum plates are welded by the TIG and MIG fusion welding process, as well as by the solid-state welding process, friction stir welding (FSW), which has recently become very important in aluminum and alloy welding. For welding AA2024-T35 with MIG and TIG fusion processes, the filler material ER 4043—AlSi5 was chosen because of reduced cracking. Different methods were used to evaluate the quality of the produced joints, including macro- and microstructure evaluation, in addition to hardness and tensile tests. The ultimate tensile strength (UTS) of the FSW sample was found to be 80% higher than that of MIG and TIG samples. The average hardness value of the weld zone of metal for the MIG- and TIG-produced AA2024-T3511 butt joints showed a significant decrease compared to the hardness of the base metal AA2024-T351 by 50%, while for FSW joints, in the nugget zone, the hardness is about 10% lower relative to the base metal AA2024-T3511.

Adhesive bonding has proven to be a reliable method of joining materials, and the development of new adhesives has made it possible to use bonding in a variety of applications. This article addresses the challenges of bonding metals such as the aluminum alloy EN AW-5754 and the stainless steel X5CrNi18-10. In this study, the effects of laser cleaning and texturing on the surface properties and strength of two bonded joints were investigated and compared with mechanical preparation (hand sanding with Scotch-Brite and P180 sandpaper). The bonded joints were tested with three different epoxy adhesives. During the tests, the adhesion properties of the bonded surface were determined by measuring the contact angle and assessing the wettability, the surface roughness parameters for the different surface preparations, and the mechanical properties (tensile lap-shear strength). Based on the strength test results, it was found that bonded joints made of stainless steel had 16% to 40% higher strength than aluminum alloys when using the same adhesive and surface preparation. Laser cleaning resulted in maximum shear strength of the aluminum alloy bond, while the most suitable surface preparation for both materials was preparation with P180 sandpaper for all adhesives.

Sustainable joining technologies are important manufacturing processes for the production of high-quality joints of electrical connections. High-quality connections must have high electrical and thermal conductivity to reduce energy losses during their lifetime, they must have high mechanical properties to achieve a long service life, and they must be manufactured with lower energy consumption. In this article, the properties of solid wire electrical contacts produced by ultrasonic welding and soldering were compared. Ultrasonic welding of thin solid copper wires was performed with a copper ring. A particular focus of this study is on the energy used to produce these joints. The research included electrical resistance, peel strength and tensile strength tests, The results of the electrical resistance showed similar electrical resistance between the two processes. The result of mechanical strength shows that ultrasonic joints achieved higher mechanical strength. The most important result is that ultrasonic welding consumed only 11% of the energy to produce the joint compared to soldered joints.

This paper aims to compare the mechanical and structural properties of butt-welded properties of dissimilar aluminum alloys 2024-T351 and AA 6082-T6 obtained by MIG and TIG welding processes. Alloy AA 6082 T6 is well weldable by classic fusion welding processes (MIG and TIG), while alloy 2024-T351 is almost non-weldable. For the welding of these two different Al alloys, MIG and TIG welding procedures were used on 8 mm thick sheet metal using additional material 4043A (AlSi5) and a mixture of argon and helium as a protective gas for the MIG welding process, or pure argon for the TIG welding process. The paper compares the mechanical properties of welded joints obtained by MIG and TIG welding. The microstructural evolution of the welded joint of dissimilar aluminum alloys AA6082-T6 and AA2024-T351 is compared. The mechanical properties of welded joints of dissimilar aluminum alloys are compared based on the results of Vickers hardness tests, tensile and bending tests of welded samples.

Multi-material design was developed as a modern design concept for lightweight structures (Lightweight design - LW) which aims to integrate different types of materials into one structure. The main problem when joining sheets made of different, i.e. dissimilar materials, primarily steel and aluminum alloys, are the different mechanical, physical and chemical properties of the materials being joined. Through this paper, the state of the art will be analyzed when it comes to modern technologies for joining steel and aluminum alloys sheets. The term "modern joining technique" refers to all innovative joining technologies that have been developed or have seen significant application in the last few years.