Research on the Compensation Method for Residual Stresses in SLM-formed Parts Considering the Thermo-mechanical Coupling Effect

Introduction: In the selective laser melting process, metal powders rapidly absorb energy, melt, and solidify. This rapid thermal cycling causes defects like balling, warping, and cracking, significantly increasing residual stresses and degrading part quality and performance. This study aims to improve the quality and performance of selective laser melting-formed parts by developing and validating a strategy to compensate for detrimental residual stresses. Method: A mathematical model of the temperature field and stress field during selective laser melting forming was established. Stress was simulated under various process parameters using Simufact Additive software. A residual stress compensation strategy utilizing external magnetic fields was proposed. The rationality of this magnetic field-based strategy was then verified using Comsol Multiphysics software. Results: The simulation results demonstrated the significant influence of process parameters on residual stress generation. The verification performed in Comsol Multiphysics confirmed that the proposed external magnetic field compensation strategy is rational and sound. Discussion: This work pioneers an active stress-control strategy for SLM, offering a practical solution to residual stress challenges and enhancing industrial applicability for critical components. Conclusion: Implementing an external magnetic field compensation strategy effectively mitigates residual stresses in selective laser melting, leading to substantial improvements in the quality and performance of the manufactured parts.