The tensile tests under superplastic temperature of BTi-62421S titanium alloy were carried out. Me
chanical property, metallurgical structure and morphology of failure surface were investigated to determine the fracture
mechanism and the optimum parameter of superplastic forming. Based on these researches, a BTi-62421S titanium
alloy frame was superplasticly formed. The results show BTi-62421S titanium alloy has the optimal superplastic per
formance with an extensibility of 448. 5% when deformed at the temperature of 920 ℃and the strain rate of 1伊10- 3 /
s. The gliding fracture is the main mode during the fracture procedure, accompanied with the character of brittle frac
ture on some conditions. A BTi-62421S titanium alloy frame satisfying the operating requirement can be formed suc
cessfully at the optimal superplastic condition.