Numerical simulation and extracting the statistical model indicating the effect of laser beam diameter and workpiece thickness on temperature distribution in laser welding in titanium alloy

Nowadays, the use of lasers in welding titanium alloys has special applications in high-tech industries. This study aims to extract the statistical model showing the effect of changes in the diameter of laser beam diameter and distance in line thickness welding temperature. At first, For establishing this model, the required experiments were designed by the Taguchi method and then evaluated using the finite element method. The surface response method is used to extract the statistical model based on the variation of laser beam diameter and distance through the workpiece thickness. By the analysis of the variance, the statistical model error was evaluated in an acceptable range. According to the evaluated results, the influence percent of the distance along with the workpiece thickness and the laser beam diameter is 76.67 and 97 %, respectively, on the welding temperature. By increasing the diameter of the laser beam, the amount of the welding temperature is significantly reduced. For laser welding of Ti6Al4V, the best laser beam diameter is between 0.2 and 0.24mm.