Distribution Characteristics of In-Grain Misorientation Axes in Cold-Rolled Commercially Pure Titanium and Their Correlation with Active Slip Modes

The distribution characteristics of in-grain misorientation axes (IGMA) in cold-rolled pure titanium were investigated using electron backscatter diffraction (EBSD). Depending on the orientation of individual grains, two distinct IGMA distribution patterns were observed: one with strong intensities of IGMA around aY0001aY (c) and the other with those around aYuvt0aY (c). Analyses based on the Taylor axes and Schmid factors of possible slip modes suggested that the former pattern arises from predominant activation of prism aYaaY (c) slip, while activation of {11 $(2) over bar $2} ($(1) over bar $$(1) over bar $ 23) slip under the suppression of prism (a) slip results in the latter pattern. It was also found that prism (a) slip becomes more active with increasing strain, playing a critical role in the plasticity of pure titanium. The present work demonstrates that IGMA analysis of EBSD data may be used to explore the active slip mode in polycrystalline hexagonal-close-packed (hcp) metals deformed to moderate to large strains.