抄録
The Formability of titanium alloy sheet in the multistage deep drawing was investigated. In the titanium alloys, the beta titanium alloys have good cold workability in the metal forming. However, a seizure tends to occur during metal forming due to high reactivity with other metals. In this study, to improve the formability of titanium alloy sheet, the formability in multistage deep drawing process of beta titanium alloy was investigated. The blank used was the commercial beta titanium alloy Ti-15V-3Cr-3Sn-3Al. To prevent the occurrence of seizure, the blank treated by oxide heating was used. The effects of the surface roughness and hardness on the formability in the multistage deep drawing processes were examined. The improvement of surface roughness of drawn cup was also attempted by using heat treatment. A long titanium alloy cup was successfully formed by intermediate annealing at the 3rd stage. It was found that the drawn cup by multistage deep drawing could be formed to the 6th stage.
