Deformation Mechanism and Microstructure Evolution of TLM Titanium Alloy during Cold and Hot Compression

摘要:

研究了在应变速率0.001 s-1条件下，TLM钛合金在室温压缩和850 ℃热压缩的形变机理和组织演变规律。实验结果表明：TLM钛合金在冷压缩和热压缩条件下具有不同的形变机理和组织演变规律。在冷压缩过程中，TLM钛合金的形变特征主要是孪生、应力诱发马氏体转变及位错滑移；在850 ℃热压缩过程中，TLM钛合金的形变机理主要是位错滑移、动态回复和动态再结晶。在热压缩过程中，流变应力的软化过程与压缩过程中的动态回复和动态再结晶有关。TLM钛合金在冷压缩和热压缩条件下的抗压缩强度分别为975和40 MPa；相比冷压缩强度，TLM合金在850 ℃条件下的热抗压缩强度降低了96%

Abstract:

The deformation mechanism and microstructure evolution of TLM titanium alloy were studied during cold compression at room temperature and hot compression at 850 oC under the condition of 0.001 s-1 strain rate. The results show that the deformation mechanisms and microstructure evolution under cold and hot compressions of TLM alloy are different. Twinning, stress-induced α" phase transformations and dislocations slipping are the main deformation feature in cold compression, whereas the dislocations slipping, dynamic recovery (DR) and dynamic recrystallization (DRX) are the main deformation mechanisms in hot compression. The stress flow softening of TLM alloy in hot compression is related to DR and DRX. Meanwhile, the compressive strengths in cold and hot compression are 975 and 40 MPa, respectively. Compared with the cold compression, the compressive strength of hot compression is decreased by about 96%