Stress and deformation finite element method simulation of thin wall part with pre-deformation substrate during laser solid forming

Finite element method (FEM) models are established to perform transient thermo-elastic-plastic FEM analysis on stress and deformation of single-pass multilayer with and without substrate pre-deformation during laser solid forming (LSF). Simulation results show that substrate with pre-deformation can affect the distribution and size of stress and deformation in formed parts which can effectively alleviate the warpage of substrate. The point with initial tensile stress on the bottom surface of substrate has a smaller residual stress than that of the substrate without pre-deformed. The middle position of the interface between the substrate and the cladding layer also has a smaller residual stress than that of the substrate without pre-deformation. In both models, the positions of maximum residual compressive stress are different. Both sides of cladding layers deform badly compared with the middle location. The first cladding layer has the largest effect on substrate deformation; the deformation of the substrate gradually reduces as the cladding process proceeds. The longitudinal displacement change rate of the substrate constantly reduces and eventually tends to stable. Appropriate pre-deformation of the substrate before LSF can effectively control deformation of the substrate and improve stress distribution of the part.