Parameters optimization and objective trend analysis for fiber laser keyhole welding based on Taguchi-FEA

This paper proposes an integrated method for process parameters optimization and objective analysis in the fiber laser keyhole welding based on Taguchi and finite element method (FEA). The Taguchi-FEA framework is established and applied for the objective of increasing the ratio of weld penetration to width (P/W) in the welded joints. Numerical simulations are incorporated into identifying the desired responses and the process parameters effects on the objective without consuming time, materials, and labor effort. To validate the effectiveness of the integration methodology, the fiber laser keyhole welding of the hot-dip galvanized dual phase sheet (GA-DP590) has been carried out in this paper. The three process parameters, laser power (LP), welding speed (WS), and focal position (FP), have been taken into consideration during the optimization process. The optimized results are confirmed, and trend of the objective variation near the optimal process parameters is analyzed by the numerical simulation. The corresponding microstructure, phase transformation and microhardness variation of the optimized weld bead are also calculated. The results demonstrate that the proposed method is reliable and effective for improving the quality of welded joints in the practical production level.