Fixture Locating Modelling and Optimization Research of Aluminum Alloy Sidewall in a High-Speed Train Body

The high-speed train body is welded with aluminum alloy assemblies or parts. Due to the material properties, the welding deformation is much significant. In order to control the welding deformation, this paper takes the sidewall welding of a high-speed train body as the research objective, and carries out the fixture locating modelling and optimization research of the aluminum alloy sidewall. Firstly, a finite element model of the sidewall is established and verified by the comparison between the analysis results and the actual measurement data. Then the residual stress and deformation of the sidewall after welding are analyzed. By selecting the longitudinal parameters of different fixture locating layouts for welding analysis, models describing the relationship between the maximum welding residual stress and maximum welding deformation and the longitudinal fixture locating distance of the sidewall are established. Finally, the fixture locating model of welding deformation is used to optimize the longitudinal fixture locating distance. And the transverse fixture locating distance is also optimized by comparing different locating positions. The result shows that the welding residual stress and the welding deformation have been decreased in the optimal fixture locating layout.