Multi-response Optimization of CO2 Laser Welding of Rene 80 Using Response Surface Methodology (RSM) and the Desirability Approach
M. Moradi and M.M. Fallah
Recently several efforts have been made for optimizing the laser welding process of superalloys due to their wide applications in the industry. In order to achieve the appropriate properties of weldments, the input parameters of the laser welding process should be studied and optimized. The present study was aimed at the statistical optimization of CO2 laser butt joint welding of Ni-based super alloy Rene 80. So, the input parameters laser power, welding speed, laser beam focal point position and inert gas pressure have been optimized for achieving proper weld geometry comprised of welding surface width, welding pool area, welding width of heat affected zone (HAZ), weld undercut and drop of welding process. For modelling and optimizing of process parameters, the response surface methodology (RSM) benefiting from the desirability approach was utilized. Verification experiments were carried out in order to analyse the optimization results and the welding geometry, mechanical properties of tensile strength and microhardness of samples were studied.
Keywords: CO2 laser, Ni-based super alloy, Rene 80, laser welding, geometrical dimensions, optimization, response surface methodology (RSM), desirability approach