A FEM model to study the fiber laser welding of Ti6Al4V thin sheets

This paper describes a finite element model for fiber laser beam welding of Ti6Al4V in butt configuration. Full penetration keyhole welding of 2-mm-thick plates was performed by adopting a Yb-YAG fiber source. Neither filler wire nor groove preparation was adopted to perform the seam. Various welding conditions were considered in order to develop a versatile and simple model for the heat source. Thus, the study was carried out by varying the modeling strategy of the thermal source as a function of the calculated expected seam geometry. ANSYS parametric design language (APDL) programming was used for the generation of the numerical code. The calibration of the model involved both cross-section geometry and thermal cycle beside the weld seam. The accuracy was improved by simulating the thermal contact conductance at the interface. Transient temperatures and geometric characteristics of the weld zone were calculated. Numerical results were in good agreement with experimental ones.