Mechanical behaviour and microstructural evolution of Ti-37 at.%Nb alloy subjected to hot compression deformation

Abstract As a typical commercial superconducting alloy, Ti-37 at.%Nb alloy is put into engineering application after it experiences plastic deformation at high temperatures. In order to interpret flow behaviour of Ti-37 at.%Nb alloy at elevated temperatures, the constitutive equation of the alloy is constructed based on compressive test at the temperatures (700–1000 °C) and the strain rates (0.0005–0.5s−1), where strain compensation is taken into consideration. According to the corresponding constitutive equation, flow stress of Ti-37 at.%Nb alloy is accurately predicted, which is further validated by the experimental data. Simultaneously, the involved microstructural evolution of Ti-37 at.%Nb alloy is characterized in order to further reveal thermal-mechanical behaviour and plastic deformation mechanism of the alloy. Discontinuous dynamic recystallization (DDRX) and continuous dynamic recystallization (CDRX) are found at the same time during hot plastic deformation of Ti-37at.%Nb alloy. Plastic deformation and dynamic recrystallization have a comprehensive influence on textures of Ti-37 at.%Nb alloy. {100} , {100} , {111} and {111} textures are observed in all the deformed Ti-37 at.%Nb samples, where Ti-37 at.%Nb specimens deformed at 700, 900 and 1000 °C exhibit the strongest {100} texture, whereas Ti-37 at.%Nb specimen deformed at 800 °C shows the strongest {111} texture.