Ti─17合金高温变形机理研究

An Investigation on Hot Deformation Mechanism of Ti-17 Alloy

用热模拟压缩试验研究了Ｔｉ－１７合金高温变形特点，通过金相组织和ＴＥＭ观察发现，β区变形是以扩散回复型变形机制占主导地位；高应变速率下只发生动态回复；低应变速率下发生连续再结晶。（α＋β）区变形是界面滑移，高应变速率下易发生动态再结晶。试验还确定了变形激活能Ｑ和应变速率敏感因子ｍ值，β和（α＋β）区中分别为１６１ｋＪ／ｍｏｌ、４３７ｋＪ／ｍｏｌ和０．３２、０．２５。

The high temperature deformation characteristic Ti-17 alloy was investigated using hot compressive test.BY metallographic and TEM observation,it was found that in β region the dominant deformation mechanism was dynamic recovery characteristic of diffusion,at high strain rate,only dynamic recovery operated,while at low strain rate,continuous recrystallization took place,In(α+β)region,the interface slip was dominant deformation mechanism which resulted in dynamic recrystallization at high strain rate.The apparent deformation activation energy Q and strain rate sensitivity m were also calculated,which were 161kJ/mol and 437KJ/mol,0.32 and 0.25 in β and(α+β)region respectively.