Origins of Microtexture in Duplex Ti Alloys (Preprint)

摘要

A previously developed methodology was used to transform electron backscatter diffraction (EBSD) data for the primary and secondary alpha phases of Ti-6Al-2Sn-4Zr-6Mo (Ti-6246) to the prior beta phase. The results established that the observed microtexture in duplex alloys is a direct result of the prior beta grain orientations, and variant selection. In addition, for a homogeneous duplex microstructures, all of the secondary alpha phase and the majority of the primary alpha grains retain crystallographic coherency, according to the Burgers Relationship, with the surrounding beta-phase matrix which comprise prior beta grains. This investigation establishes that this technique to recover the prior beta grain orientations is applicable to duplex alpha/beta titanium microstructures. The crystallographic coherency of the primary and secondary alpha phase with the prior beta grain coupled with variant selection then leads to the localized microtexture observed in a wide variety of Ti alloys.