Welding of stainless steel with pure copper by Nd:YAG laser, optimizing the tensile strength

Abstract

Welded joints of copper and stainless steel has very important applications in the industries. In this project, laser welding of copper and stainless steel was carried out at different values of beam power, speed of the beam and pulse duration. A 9 kW ALPHALASER AL200 Nd:YAG was used to weld 1.5mm thick stainless steel plates and 1.6mm thick copper plates. Tensile testing of the specimen was done using universal testing machine(UTM) to find out the peak load at which the specimen breaks. The results were analysed using signal to noise ratio and multiple regression analysis for optimum parameters and degree to which each factor contributes respectively. Equation is found out to depict the relation between tensile strength, beam power, speed of the beam and pulse duration. Results indicate that tensile strength increases with increase in beam power and pulse duration, and decreases with increase in laser speed.