Room-temperature creep anisotropy in hot-rolled commercially pure titanium plate

Room-temperature creep testing was performed on a commercially pure hot-rolled titanium plate in three orthogonal directions. The rolling direction (RD) exhibited a strong prismatic texture, while the transverse direction (TD) and normal direction (ND) showed a pronounced basal texture. Over 50 hours of testing at normalised stress values, TD and ND samples accumulated less creep strain with lower creep strain rates than RD samples, indicating anisotropy. Electron Backscatter Diffraction, coupled with slip trace analysis, revealed that grains with their c-axis not aligned with the loading axis (soft orientation) deformed via prismatic slip, while grains with their c-axis nearly parallel to the loading axis (hard orientation) either remained undeformed or deformed via extension twinning. Occasional activation of pyramidal <a > and multiple prismatic slip systems were observed in constrained areas of hard- and soft-oriented grains at the highest applied creep stresses. The Luster-Morris parameter indicated varying ease of slip transmission based on the misalignment of slip direction and slip plane normal across grain pairs. The creep anisotropy is due to different fractions of soft- and hard-oriented grains in the investigated directions. © 2024 Informa UK Limited, trading as Taylor & Francis Group.