Thermo-mechanical modeling of thermal stress in metal additive manufacturing considering elastoplastic hardening

Abstract The build-up of thermal stress induced by a high-temperature gradient in an additively manufactured part during laser metal additive manufacturing provides significant limitations to the adoption of this process since thermal stress may induce high tensile residual stress and part distortion in the additively manufactured parts. Herein, a thermomechanical analytical model is proposed to predict the in-process elastoplastic hardening thermal stress and strain for single-track scan strategy. The thermal model is validated using experimental results of melt pool geometry. Also, finite element simulation is performed to validate the proposed elastoplastic hardening thermal stress model of the same problem.