Quantitative prediction of grain boundary misorientation effect on twin transmission in hexagonal metals

Intergranular twinning shear transmission through twin-twin accommodation, which plays an important role on microstructure evolution, is often observed in deformed hexagonal metals. The shear transmitted between two connected twins is m′s, where m′ is the geometrical compatibility factor and s is the magnitude of the original shear. However, the quantitative correlation between the grain boundary misorientation (GBM) and m′ factor for shear transmission is unknown. In the present study, we developed an m′-GBM map to tackle this problem. The map is applied to {112¯2}–{112¯2}, {112¯2}–{112¯4} and {112¯4}–{112¯4} twin pairs in Ti, which have rarely been reported before but are profuse in a cryorolled state. Favorable GBM for the formation of these twin pairs is revealed by the map. Specifically, the map shows that low GBM angles (