Estimation of Residual Stress in Selective Laser Melting a Zr-Based Amorphous Alloy

Abstract: 

An accurate estimation of residual stresses is crucial to ensure dimensional accuracy and prevent premature fatigue failure of 3D printed components. Different from their crystalline counterparts, the effect of residual stress would be worse for amorphous alloys owing to their intrinsic brittleness with low fracture toughness. While the generation of residual stress and its performance in 3D printed amorphous alloy components still remains unclear. Here, finite element method combined with experiments and theoretical analyses were introduced to estimate the residual stress in selective laser melting a Zr-based amorphous alloy. The results revealed that XY cross scanning strategy exhibits relatively low residual stress by comparison with X and Y strategies, and the residual stress becomes serious with increasing bar thickness. The residual stress, on the other hand, could be tuning by annealing or preheating substrate. The above scenario is in-depth understood according to temperature gradient mechanism and its effect on microstructure evaluation.