Multi-scale simulation of residual stress and deformation of large-size hollow parts fabricated by laser-based powder bed fusion

Hollow structures are widely used in aerospace, automotive, and other fields. Laser-based powder bed fusion (LB-PBF) enables the fabrication of complex parts. However, residual stresses and deformations present challenges for manufacturing high-quality components. This study proposes a modified inherent strain method (MISM) coupled with shear strain and dynamic mechanical properties to capture the asymmetric deformation behavior of the parts. The asymmetric deformation behavior was verified by two typical geometric structure parts, which demonstrated the generality of the phenomenon. The excellent agreement between the experimental and predicted results proved the validity of the extended model. Based on the asymmetric deformation, the effect of different geometries on the stresses was investigated. The results showed that the geometry of the parts affects the stress distribution and magnitude. The proposed numerical model can accurately predict the stress components of the parts, which is helpful to further investigate crack extension and damage in complex thin-walled parts.