Abstract: Key parts' distortion of an ultra-high strength steel aviation part cannot meet the design requirements (±1 mm) after heat treatment due to its complex initial configuration. To solve this problem, the heat treatment distortion of parts in different configurations was studied by means of simulation. The results show that the overall cooling of the initial configuration of the part is first fast and then slow, with higher stresses in the thick-walled part and relatively low stresses in the thin-walled part, and the largest distortion of 2.16 mm in the tail. Through iterative optimization of the finite element model, the simulation results show that the maximum distortion of the critical part is reduced from 2.16 mm to 0.90 mm, and the optimized part configuration is finally obtained. Based on the optimized configuration, the part is verified in actual production, and the actual distortion of each feature point of the part meets the design requirements, and the simulation results match well with the actual production results, which verifies the accuracy of the constructed finite element model and the effectiveness of the heat treatment simulation technology in the optimization of the configuration state.

Key words: ultra-high strength steel, complex parts, distortion, simulation, configuration optimization