# Evolutionary Algorithm to Optimize Process Parameters of AI/Steel Magnetic Pulse Welding
###### Abstract  
The Magnetic Pulse Welding (MPW) process uses only electromagnetic force to create a solid-state metallurgical bond between a working coil and outer workpiece. The electromagnetic force drives the outer tube to collide with the inner rod, resulting in successful bonding. However, due to the dissimilarity of the MPW joint, only a portion of the interface forms a metallurgical bond, which affects the quality of the joint. Therefore, the purpose of this study is to analyze the effects of process parameters on joint quality through experimental work using RSM. Furthermore, an optimization algorithm is utilized to optimize the process parameters used in magnetic pulse welding. A1070 aluminum and S45C carbon steel were used as the materials, while peak current, gap between working coil and outer tube, and frequency were chosen as the process parameters for MPW. The welding conditions are determined through experimental design. After welding, the maximum load and weld length are measured to analyze the effect of the process parameters, and a prediction model is developed. Specifically, to achieve a high-quality joint, the process parameters are optimized using the Imperialist Competitive Algorithm (ICA) and Genetic Algorithm (GA). The results reveal that the peak current is a significant parameter, and the developed prediction model exhibits high accuracy. Furthermore, the ICA algorithm proves very effective in determining the process parameters for achieving a high-quality AI/Steel MPW joint. magnetic pulse welding; evolutionary algorithm; electromagnetic force; process parameters; Imperialist Competitive Algorithm; Genetic Algorithm +
Footnote †: journal: Applied  
compound (IMC) layers between materials but also cracking, porosity, and oxidation [5]. For this reason, friction stir welding, explosive welding, and magnetic pulse welding have recently been widely studied as methods of solid-state welding. [PERSON] et al. [6] conducted a numerical analysis to investigate the process of mass transfer and material mixing in friction stir welding of dissimilar joints. [PERSON] et al. [7] attempted to join aluminum alloy to DHP copper using friction stir welding. This process has the capability to produce high-quality joints between different combinations of materials. However, due to tool conditions, several types of defects may occur in joints, such as thickness reduction and flash and keyhole defects [8]. Explosive welding utilizes explosive force to create a successful metallurgical bond between workpieces. [PERSON] et al. [9] reported on the welding of magnesium and aluminum alloys using an inclined arrangement in explosive welding, while [PERSON] et al. [10] studied the effect of flyer material on interface phenomena in explosive welds of aluminum and copper. However, controlling the process parameters is difficult, and experimental work can be unsafe. For this reason, Magnetic Pulse Welding (MPW), a solid-state welding process, has been used in the development of high-quality dissimilar joints. MPW is a high-velocity welding process using an electromagnetic force to cause high-velocity collisions between dissimilar materials, resulting in true metallurgical bonds. MPW uses only electromagnetic force, without filler wire, as shown in Figure 1. It is an environmentally friendly welding process [11; 12]. When using MPW for the welding of dissimilar materials such as aluminum and steel, a challenge for researchers is selecting the proper welding parameters to create strong joints with excellent properties. The main process parameters of MPW, including input current, gap between workpieces, and frequency, play important roles in determining joint quality. One weakness of MPW is its potentially short metallurgical bond length. Thus, analysis of the effect of process parameters on weld length is important to obtain high-quality joints. [PERSON] et al. [13] characterized and analyzed the interface structure of an Al/Ta joint, while [PERSON] et al.