The Effect of Heat Treatment on the Evolution of Microstructure and Texture in Ti80 Hot Rolled Pipe

In this study, the microstructure and texture evolution of hot rolled Ti80 pipe annealing at 960°C and 990°C in α+β two-phase field have been investigated. The results showed that the dissolution of α phases induced the increase of texture components of primary α phases (αP) and the αP were the main factors that determine the final texture at 960°C. At 960°C, the microtextures of secondary α phases (αS) were very close to that of αP. As the annealing temperature increased to 990 °C, the main factors affecting the microtextures of αS changed from the αP to the recrystallized β grains. The textures of β phases were greatly influenced by the annealing temperature. The β phases at high temperature were not mainly from the grow up of residual β phases. It was formed by the transformation of α phases at room temperature. Consequently, this study could provide some ideas for decreasing the texture intensities of hot rolled Ti80 pipes, such as reducing the area of α colonies before rolling, scattering the crystal orientations of αP, and controlling the size of recrystallized β grains.