Ti1023合金高温塑性变形力学行为及组织演变的研究

Study on Mechanical Behavior and Microstructure Evolution of Ti1023 Alloy During High Temperature Plastic Deformation

通过Ti1023合金热模拟压缩试验,得到不同高温变形条件下的真应力-应变曲线。并对经变形和热处理的合金的组织演变规律进行了研究。结果表明：高温变形过程中,Ti1023合金的流变应力对变形工艺参数较为敏感,且在不同变形条件下,应力-应变曲线的变化呈现一定的规律,在低温和较高应变速率下,曲线多呈现动态再结晶特征;在高温条件下,曲线多呈现动态回复特征。随变形温度的升高,α相时效析出量逐渐减少,形态由等轴/条片状逐步演化为长条状;随应变速率的提高,α相形貌逐渐变为长条状,且相尺寸减小。不同形貌的α相会对合金的性能产生不同的影响,且在中温区（760~780℃）变形后可得到良好综合性能的组织。

The true stress-true strain curves were obtained through the isothermal compression experiment of Ti1023 alloy. And the microstructure evolution law of the alloy after deformation and heat treatment was studied. The results show that in the process of high temperature deformation, the flow stress of Ti1023 alloy is sensitive to deformation parameters, and the stress-strain curves show a certain regularity under different deformation conditions. Under the condition of low temperature and high strain rate, the stress-strain curves show dynamic recrystallization characteristics. And the curves are dynamic recovery characteristic at high temperature. With the increase of deformation temperature, the amount of α-phase precipitation gradually decreases and the shape is gradually evolved from the equal axis or sheet to a long strip. With the increase of strain rate, the α-phase morphology gradually evolves into a long strip and the size decreases. Different morphologies of the α-phase have different effects on the properties of the alloys, and the microstructure of good comprehensive performance can be obtained after the deformation at the middle temperature zone（760-780℃）.