Numerical investigation of thermo-mechanical-phase interaction in laser melting additive manufacturing process incorporating phase-field framework

In this study, we propose a multiphysics coupling model for simulating heat conduction, thermoelasticity, and solid-liquid phase transitions during selective laser melting (SLM). The model employs a heat conduction equation to characterize the evolution of the temperature field during the laser scan, incorporating latent thermal effects and dynamical properties of the laser heat source. Thermoelastic equations are used to describe the strain response and stress evolution induced by the temperature field. Additionally, phase-field equations simulate the dynamic behavior of the solid-liquid phase interface and microstructural evolution, accounting for thermally driven forces due to high temperatures and latent heat, as well as the virtual strain energy resulting from thermoelasticity. The proposed model is compatible with SLM processes, incorporating key parameters such as laser power and scanning speed to ensure consistency between digital and physical quantities. Numerical tests validate the capability of the model to accurately simulate temperature field dynamics, hierarchical structure evolution, thermally induced microstrain, and macroscopic stress evolution during SLM processes.