关键词: 增材制造, 激光选区熔化, 大尺寸薄壁件, 仿真分析, 变形控制, 晶格结构

Abstract: Simulate Additive software was used to simulate and analyze the additive manufacturing processes of a typical large-sized thin-walled component—exhaust pipe. The results show that the SLM formed exhaust pipe parts without constraints have high residual stress and significant deformation. The post-processing releases residual stress in the parts, but the overall deformation of the parts further increases to 3.5 mm, with a maximum deformation of 9 mm. A lattice structure was introduced with high specific strength and stiffness as an auxiliary structure for controlling deformations, and a lattice processing scheme was designed with sufficient resistance to deformation and may be removed through post-processing. The cell type is QuadDiamond, the rod diameter is  as 1.3 mm, the rod length is as 19 mm, and the width of the lattice region is about 60 mm. The SLM test results of the exhaust pipe parts under lattice constraints are quite consistent with the numerical simulation results. The cloud image results of the three-dimensional scanning show that the overall deformation of the part is about 1 mm, and the maximum deformation does not exceed 2.5 mm, meeting the requirements for the part use. The above results show the effectiveness of using lattice structure in deformation control of large-sized thin-walled parts formed by SLM. 

Key words:  , additive manufacturing, selective laser melting(SLM), large-size and thin-wall part, simulation analysis, deformation control, lattice structure