Investigation of the joint length of weldment of environmental-friendly magnetic pulse welding process

Among various sustainable processes, the magnetic pulse welding (MPW) is gaining popularity over the years due to its ability of joining two similar/dissimilar metals using the electromagnetic forces. Past studies extensively reported the use of experiments but limited numerical modeling based on finite element analysis for studying the quality of the weld with respect to individual and/or combined effect of impact velocity, impact angle, current, frequency, and electromagnetic force distribution. One such important application of this process is in the refrigerant tube where determining the desired Al/Cu joint length is essential. It was noticed that the extensive studies were done for selecting the desired joint length along the circumferential direction under specific materials, while very limited studies were carried on the joint length along the longitudinal direction. Therefore, the present work introduces the experimental and numerical framework based on genetic programming (GP) to measure and quantify the joint length along the longitudinal direction for refrigerant tube as a function of the gap between coil and outer tube, positions of the tube and impact angle. Further, the performance of the three complexity terms used in objective functions of GP was investigated in the formation of joint length models. The main and interactive relationships between the joint length and gap between coil and outer tube, positions of the tube, and impact angle are revealed. The experiment findings, model formulation, and the relationships of joint length will assist experts in monitoring the MPW effectively to obtain a high quality weld characteristic.