可在400～500℃使用的TC4-B钛合金棒材研制

Development of TC4-B Titanium Alloy Bars Applied in 400 ℃ to 500 ℃

通过在TC4钛合金中添加Si、O、Mo、Zr、Sn合金元素，研制出名义化学成分为Ti-6Al-4V-0．3Si-0．3Mo-0．3Zr-O．3Sn-0．150的TC4-B钛合金。并采用两种镦拔组合变形工艺，制备尺寸为妒5mm圆棒和51mm×85．6mm扁方棒。结果表明：经“三三一”工艺锻制的TC4-B钛合金棒材显微组织更为均匀；力学性能明显优于经常规工艺锻制的棒材，其室温拉伸强度可达1000MPa以上，500℃时拉伸强度可达636MPa，伸长率为18％，断面收缩率为61％，可在400～500℃高温条件下使用。

TC4-B titanium alloy with the nominal chemical composition of Ti-6Al4V-0. 3Si-0. 3Mo-0. 3Zr-0. 3Sn- 0. 150, was successfully developed by adding Si, O, Mo, Zr and Sn elements into TCA titanium alloy. And the TC4-B titanium alloy bars with dimension of Ф75 mm and 51 mm × 85.6 mm were successfully developed by the two different forging processes. The testing results show that the TC4-B titanium alloy bars which produced by ＂331＂ process have more homogeneous microstructure and better mechanical properties. The room-temperature tensile strength can reach 1 000 MPa, the tensile strength at 500 ℃ can reach 636 MPa, elongation is 18%, reduction of area is 61%, which all could meet the requirement of working under 400 ℃ to 500 ℃.