BT22钛合金及其大型锻件的研究进展

Research Progress of BT22 Titanium Alloy and Its Large Forgings

综述了国内外BT22合金及其改型合金的应用现状,归纳介绍了BT22合金的锻造加工及热处理工艺。结果表明,BT22合金在两相区低于β_转15～50℃的温度范围内多火次锻造,每火次变形量不低于60%。通过严格控制变形速率和终锻温度可制备出组织均匀、晶粒细小的锻件,经两阶段整体热处理后可获得强度、塑性和韧性的最佳匹配。针对我国的研究现状指出了BT22合金大型锻件制备方面亟待解决的问题和未来研究发展的方向。

Application state of BT22 alloy and its modification alloy is summarized. The forging processing and heat treatment technology of BT22 alloy are introduced. The results indicate that the BT22 bars microstructure can be refined through α ＋β phases forged （lower thanβ T by 15- 50 ℃ ） with good structure homogeneity. Control the rate of deformation and final forging temperature strictly in processing, and the deformation value at every forging time is greater than 60%. Finally, the two-stage annealing makes BT22 forgings have best matching of strength and plasticity, and have high KIC value. Moreover, several urgent problems and further research direction of BT22 alloy large forgings preparation are put forward.