关键词: 高速级进拉深, 应变率效应, 率相关本构, 纯钽薄板

Abstract: In view of the formability problems caused by the strain rate effects in the high-speed stage deep drawing process of pure tantalum thin-wall members, the identification of the constitutive model was carried out, and the Johnson-Cook depth-forming model was constructed considering the strain rate effects of materials. The results show that the pure tantalum sheet shows an obvious strain rate reinforcement effect, and the yield strength under dynamic loading is much higher than that under the quasi-static stretch. The thermal coupling simulation and forming experiments of high speed stage deep drawing of tantalum capacitor shells were carried out. The results indicate that the simulation results of wall thickness distributions are relatively consistent with the experimental ones, and the wall thickness of the final pieces increases when the forming speed increases; the maximum thinning area of the final drawn parts occurs in the middle areas of the cylinder walls, where the highest temperature is positively correlated with the forming speed; the metallographic structures of the final shapes do not change significantly at different forming speeds, with only change the grain shape and size of different deformation areas.

Key words:  , high-speed stage deep drawing, strain rate effect, rate dependent constitutive, pure tantalum plate