Superplastic Forming Technology of Box-shaped Piece of High-temperature Titanium Alloy BTi6431S

The superplastic parameters of titanium alloy BTi6431S was obtained using sudden rate changing technique in superplastic temperature range.On the basis of tensile test,the formability of titanium alloy BTi6431S was analyzed and the superplastic forming of box-shaped piece of BTi6431S sheet was simulated with the aid of finite element analysis software Marc2003.Then,the process of superplastic forming was tested.The results show that the titanium alloy BTi6431S has good superplasticity with m=0.5,δ=306.1% and flow stress σ=71.2 MPa at about 865 ℃ and =1.5×10-4 s-1,and could form deep box-shaped pieces with good quality.