Finite Element Analysis of Pulsed Laser Bending: The Effect of Melting and Solidification

Abstract

This work developes a finite element model to compute thermal and thermomechanical phenomena during pulsed laser induced melting and solidification. The essential elements of the model are handling of stress and strain release during melting and their retrieval during solidification, and the use of a second reference temperature, which is the melting point of the target material for computing the thermal stress of the resolidified material. This finite element model is used to simulate a pulsed laser bending process, during which the curvature of a thin stainless steel plate is altered by laser pulses. The bending angle and the distribution of stress and strain are obtained and compared with those when melting does not occur. It is found that the bending angle increases continulously as the laser energy is increased over the melting threshold value.