工业级5083铝合金市域车车门正反胀超塑性成形工艺

Taking industrial 5083 aluminum alloy as the research object, the direct-reverse superplastic forming process of aluminum alloy outer wallboard of urban railway door was investigated. The uniaxial tensile test of industrial 5083 aluminum alloy at 400-560 ℃ with the strain rate of 5×10^-4-5×10^-3 was carried out. The results show that the industrial 5083 aluminum alloy has good high-temperature elongation, and the maximum elongation is 242% at 480 ℃ with 10^-3 s^-1. The constitutive model of 5083 aluminum alloy superplastic forming was constructed based on the stress-strain curves obtained by high-temperature tensile test. The punch and die with inserted ring applied for the direct-reverse bulging superplastic forming process were designed, and the left and right sides doors could be superplastic formed through a set of dies by matching the instered ring with punch and die. Then the finite element simulation was conducted on direct-reverse bulging superplastic forming experiment for outer wallboard of left side urban railway door by the MSC.MARC software, and with the appropriate direct-reverse bulging time and pressure, the minimum thickness is 2.56 mm which takes place at the part between the handrail and the doorframe. Finally, the direct-reverse superplastic forming process of the outer wallboard was carried out, and the outer wallboard of left side door with high accuracy and good surface quality was successfully manufactured. The minimum thickness is 2.69 mm and the maximum thickness thinning rate is 32.75%, and it takes place at the part between the handrail and the doorframe, which is consistent with the result of finite element simulation.