Effect of pre-annealing deformation on the recrystallized texture and grain boundary misorientation in commercial pure titanium

摘要

The effects of rolling reduction followed by annealing (at 650 degrees C) on commercial pure titanium sheet are investigated. The microstructure, texture and misorientation angle distributions after rolling and annealing are observed by electron back scatter diffraction (EBSD). It is found that, when the rolling deformation was low (20%) or medium (40%), a fraction of non-TD-split basal texture is inherited from the deformed state and remains even after long time (60 min) annealing. However, heavy rolling deformation (85%) causes a strong and typical TD-split basal texture in the deformed and annealed states. In addition, the misorentation angle distributions are relatively homogeneous for the recrystallized samples with a low or medium pre-annealing deformation. But with heavy pre-annealing deformation, the misorientation angle distributions exhibits two peaks, around 15-30 degrees and 70-80 degrees. The texture and misorientation angle evolution mechanisms are discussed in this work. The study shows the possibility to tailor the texture and the misorientation angle distribution of commercial pure titanium sheet by ordinary rolling process.