Parent beta grain reconstruction of globularized Ti-6Al-4V alloy

Abstract

In this study, a denoising method of smoothing spline is proposed to reconstruct parent β grain of titanium alloys as a supplement to the past literatures. The β mean orientation of the sample with bimodal microstructure can be well reconstructed with similar grain size and negligible misorientation (<1°) compared with traditional reconstruction result. The second test case deals with globularized α grains after multi-axial hot compression. Obvious β recrystallization happens inside the large prior β grain during deformation, which can facilitate the homogeneous globularization process. The mean orientation reconstruction of recrystallized β grain by smoothing spline is performed and further compared with the orientation calculated from one α colony by orientation-trace method. The maximum 20° misorientation exists due to the local orientation deviation inside both α and β grains during globularization processing. In addition, the globularization mechanism under multi-axial hot compression is analyzed. Despite the appearance of local heterogeneity between different α colonies, high globularized efficiency around 71.2% can be easily achieved by the multi-directional deformation.

Keywords

• Ti-6Al-4V
• β phase reconstruction
• Multi-axial hot compression
• Globularization
• Recrystallization