Laser shot peening forming of the whole wall panel: flexible manufacturing of the body skin of the high-speed train of the railway bureau
The body of high-speed transport equipment is a large-scale, complex-shaped, and thin-walled component, which is difficult to precisely form and manufacture, and has always been a difficult problem in the field of forming manufacturing. At present, the manufacturing of large-scale, thin-walled components mainly includes processes such as skin-type profile extrusion, pre-stretching stress relief, and drawing or creep. The existing drawing and creep forming processes require a large number of molds and inspection tools to be used according to the different shapes of different parts of different types of vehicles, with a long production cycle, high cost, poor consistency of parts, and it is difficult to apply to the forming of complex surfaces with small curvature. Therefore, the existing forming process is costly, inefficient, and the accuracy is difficult to guarantee, which is difficult to adapt to the flexible forming requirements of multi-variety and small batch of high-speed transport equipment, and is one of the important bottlenecks in vehicle body manufacturing at present.
Laser shock forming, as a mold-free forming process, has a wide range of shape adaptability, high forming accuracy, and excellent mechanical properties, providing an effective way for the precise and flexible forming of large thin-walled components for high-speed transportation equipment in small batches and multiple varieties. Taking the single-piece skin of the CR400 intelligent train driver's cab as an example, the 5 series aluminum alloy material has a size of 2.4mx0.6m, a thickness of 4mm, and a radius of curvature range of 800~850 mm. After laser shot peening forming, the free state size accuracy can be achieved within <0.5mm. Both the forming accuracy and performance meet the requirements for vehicle installation, and the vehicle installation verification was completed in April 2025.
