Effect of Deformation Temperature on the Microstructure Characteristics of alpha Phase in Ti-40Al-8Nb-0.5B Alloys

摘要

In this work, microstructure characteristics of alpha phase in Ti-40Al-8Nb-0.5B alloys (at%) after deformation in the beta and (beta+alpha) phase regions are examined. The experimental results indicate that the microstructure characteristics of the alpha phase are considerably affected by the deformation temperature. During the deformation in the beta phase area, the beta phase is not only elongated perpendicular to the compression direction, but also presents a < 100 >-< 100 > double fiber texture. After the beta ->alpha transformation, a part of the alpha phase exhibits an equiaxed morphology and the others show lath-like shapes. Due to the microstructural heredity, the alpha phase of the sample deformed in the beta phase field presents a < 11-20 >-< 10-10 > double fiber texture. In contrast, refined alpha phase with randomly distributed orientation is produced after the deformation in the (beta+alpha) phase field and this is caused by the dynamic recrystallization during the deformation process.