The effect of deformation temperature on the microstructure and crystallographic orientation evolution of Ti60 alloy after annealing

The effect of deformation temperatures, 900 & DEG;C and 980 & DEG;C, on the microstructure and crystallographic orientation evolution of Ti60 alloy with lamellar microstructure had been studied in our previous work. In this paper the characterizations of the microstructure and texture as well as the macrozone evolution after annealing at 1020 & DEG;C were studied for samples deformed at the both temperatures with 70% height reduction by optical microscope (OM), X-ray diffraction (XRD) and electron backscatter diffraction (EBSD). A fine homogenous bimodal microstructure in terms of morphology and orientation distribution was found in the sample deformed at 900 & DEG;C after annealing. In contrast, a sharp textured microstructure with macrozones was also produced after annealing in the sample that had deformation at 980 & DEG;C. Moreover, the prior & beta; texture and the primary & alpha; texture were analyzed. The formation of the main transformed & alpha; texture, <11-20> parallel to compression direction (CD) fiber texture, which was reinforced with an increase in deformation temperature, was found to be related to the <100>//CD & beta; fiber texture and variant selection effected by primary & alpha; grains. Finally, the mechanisms by which the macrozones formed for bimodal microstructure are discussed. In this study, a relationship between the microstructure and texture evolution is established to reveal the influence of deformation temperature on the microstructue and crystallographic orientation of Ti60 alloy after annealing.

Automated summary

The effect of deformation temperatures of 900℃ and 980℃ on the microstructure and crystallographic orientation evolution of Ti60 alloy has been studied. The characterizations of the microstructure and texture after annealing at 1020℃ were examined. The results showed that a fine homogenous bimodal microstructure was observed in the sample deformed at 900℃ after annealing, while a textured microstructure with macrozones was found in the sample deformed at 980℃. The formation of the main transformed α texture was related to the β fiber texture and variant selection influenced by primary α grains.