A Study on Gas Pressure for Superplastic Forming of Titanium Alloy Bellows
The complex superplastic forming (SPF) technology applying gas pressure and compressive axial load is an advanced forming method for bellows made of titanium alloy, which forming process consists of the three main forming phases namely bulging, clamping and calibrating phase. The influence of forming gas pressure in various phases on the forming process are analyzed and models of forming gas pressure for bellows made of titanium alloy are derived according to the thin shell theory and plasticity deformation theory. Using model values, taking a two-convolution DN250 bellows made of Ti-6Al-4V titanium alloy as an example, a series of superplastic forming tests are performed to evaluate the influence of the variation of forming gas pressure on the forming process. According to the experimental results models are corrected to make the forming gas pressures prediction more accurate.
Z.Y. Zhong, H. Saka, T.H. Kim, E.A. Holm, Y.F. Han and X.S. Xie
G. Wang et al., "A Study on Gas Pressure for Superplastic Forming of Titanium Alloy Bellows", Materials Science Forum, Vols. 475-479, pp. 3051-3054, 2005