Laser welding process optimization using statistical design of experiments

Laser welding is a keyhole fusion welding which is carried out through using high energy density which is caused by focusing the laser beam on the small spot point. The present study was aimed at the statistical optimization of CO2 laser butt joint welding of Ni-base super alloy Rene 80. In fact, the proper weld geometry is comprised of welding surface width (W1), welding pool area (A) and welding width of weld zone (W2) process optimization. Moreover, the optimal input parameters consist of laser power, welding speed, laser beam focal point position and inert gas pressure. In order to achieve the proper weld geometry as well as find out the optimal input parameters, the response surface methodology (RSM) was considered as one of the design of experiments methods (DOE) benefiting from the desirability approach. RSM is a set of mathematical and statistical techniques that are useful for modelling and predicting the response of interest affected by a number of input variables with the aim of optimizing this response. Solving multiple response optimization problems employing this technique involves using a technique for combining multiple responses into a dimensionless measure of performance called the overall desirability function. Minitab V.15 software was used analyzing this multiple response problem. Verification experiments were carried out in order to analyse the results obtained via software. In this study, the optimum laser welding condition was obtained in an attempt to achieving minimum welding geometric.

کلیدواژه ها:

laser beam welding ، optimization ، design ofexperiments ، response surface methodology ، desirability approach