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Successful joining of dissimilar materials is important in order to optimize mechanical properties such as strength, density, corrosion resistance, etc., for several applications. Al-alloys, particularly hardenable ones, are widely utilized in automobile and aerospace industries owing to their excellent properties. Besides all Al-alloys are light-weight they exhibit different properties. For instance, AA6061 alloy display excellent corrosion resistance whereas alloy AA7075 possesses a very high strength. Thus, it is worth to search the joinability of dissimilar Al-alloys plates and their performances. In this study, dissimilar Al-alloys joints (AA6061-O/AA7075-O and AA6061-T6/AA7075-T6) were produced using friction stir welding, which is well demonstrated to produce reliable joints in similar Al-alloy plates, employing two different sets of weld parameters. Detailed metallography, micro hardness measurements and tensile testing were conducted in order to characterize the joints obtained and to determine the effect of temper condition on joint performance. [ABSTRACT FROM AUTHOR]

Metal additive manufacturing (MAM) which is an innovative technology is presently being applied in various industries such as aeronautics-space, energy, automotive, and medicine. Metal parts are produced in three different ways in metal additive manufacturing methods. These are powder bed fusion, powder fed fusion and wire fed fusion systems. In the first two of these methods, metal or alloy powders are used as raw materials, while in the third method, the filler wire made of metal or alloys is the starting material. However, metal powders, especially alloy powders, are quite costly. This in turn makes the production of metal parts using filler wire very attractive. Another advantage of wire arc additive manufacturing (WAAM) is its potential to produce small- and medium-sized parts economically with high deposition rate. Nowadays, this innovative manufacturing technology is being considered a promising fabrication technology for manufacturing several products from various engineering materials such as titanium and its alloys, aluminum and its alloys, nickel-based alloys and steels. In this paper, studies on WAAM and commonly used metallic wires and the microstructure and mechanical properties of the parts produced by this method will be discussed. In addition, defects such as deformation, porosity and crack formation encountered in WAAM and their reasons will also be discussed. Finally, the problems which have to be overcome for a wider application of this production method in the manufacturing of metallic parts, will be summarized. [ABSTRACT FROM AUTHOR]

Welding process is often used in joining of similar and dissimilar steel sheets in the automotive industry. In these joining applications, resistance spot welding is the most commonly used welding method. There are on average around 3000 or 6000 spot welds in a car. The advantages of resistance spot welding are as follows: it is a relative clean and environmentally friendly process, suitable for automation and readily applicable, does not require filler metal, produce open flame that can cause accidents and injury, and require an expert operator. This study provides information about manuel and robotic spot welding applications which are performed on the vehicle body. It focusses on different types of spot welding electrodes used, their cooling methods, maintenance and life-cycles. In addition, spot welding optimization which is used for increasing weld quality during mass production is mentioned. [ABSTRACT FROM AUTHOR]

Welding process is often used in joining of similar and dissimilar steel sheets in the automotive industry. In these joining applications, resistance spot welding is the most commonly used welding method. There are on average around 3000 or 6000 spot welds in a car. The advantages of resistance spot welding are as follows: it is a relative clean and environmentally friendly process, suitable for automation and readily applicable, does not require filler metal, produce open flame that can cause accidents and injury, and require an expert operator. This study provides information about manuel and robotic spot welding applications which are performed on the vehicle body. It focusses on different types of spot welding electrodes used, their cooling methods, maintenance and life-cycles. In addition, spot welding optimization which is used for increasing weld quality during mass production is mentioned. [ABSTRACT FROM AUTHOR]

Welding process is often used in joining of similar and dissimilar steel sheets in the automotive industry. In these joining applications, resistance spot welding is the most commonly used welding method. There are on average around 3000 or 6000 spot welds in a car. The advantages of resistance spot welding are as follows: it is a relative clean and environmentally friendly process, suitable for automation and readily applicable, does not require filler metal, produce open flame that can cause accidents and injury, and require an expert operator. This study provides information about manuel and robotic spot welding applications which are performed on the vehicle body. It focusses on different types of spot welding electrodes used, their cooling methods, maintenance and life-cycles. In addition, spot welding optimization which is used for increasing weld quality during mass production is mentioned. [ABSTRACT FROM AUTHOR]

In parallel to continuously increasing demand for liquefied natural gas (LNG) which is a clean energy source, the use of 9% Ni steel plates is also increasing in the production of LNG storage tanks, due to their outstanding combination of properties such as excellent toughness, high ductility and cracking resistance at very low temperatures. During the welding of this material, low temperature fracture toughness should be kept at an acceptable level within the weld region including both fusion and heat affected zones. This study introduces the result of microstructural evolution in the weld region and the mechanical properties of the gas tungsten arc welded 10 mm thick 9% Ni containing low alloy steel joint produced by using a Ni-based filler wire. The microstructures evolved in the weld region were examined by extensive optical microscopy investigations. Mechanical properties and joint performance values of the welded joints were determined by detailed microhardness measurements and transverse tensile tests. Moreover, impact energy of the joint fabricated was also determined at -196 °C by Charpy impact test (Charpy V-notch test) and compared with the fracture toughness of the base plate at the same temperature. [ABSTRACT FROM AUTHOR]