Evolution of grain boundary and texture in TC11 titanium alloy under electroshock treatment

Abstract

This work investigated the evolution mechanism of grain boundaries in TC11 alloy after electroshock treatment (EST) using electron back scatter diffraction (EBSD) and transmission electron microscopy (TEM). TEM results showed that abundant α martensite (αM) phase was precipitated after EST with 0.06 s. EBSD results indicated that the percentage of high angle misorientation grain boundaries (HAGBs) in β phase increased from 3.74% before EST to 11.15% after 0.04 s EST, without evident change in proportion of α phase, which resulted from the low angle misorientation grain boundaries (LAGBs) of secondary α (αs) and β phase migrated to the α/β phase boundaries to form HAGBs during the αs to β phase transformation. The proportion of HAGBs in α phase increased from 23.16% before EST to 76.61% after 0.06 s EST, caused by the accumulation of LAGBs at the α/β phase boundaries to form HAGBs. The values for misorientation angle preference selection of α phase located around 60° and 90° were changed to 30° in HAGBs of β phase, and the texture distribution of α phase was uniform with maximum intensity of 5.47 after EST by 0.06 s