The processing of pure titanium through multiple passes of ECAP at room temperature

Commercial purity titanium was processed through up to 8 passes by equal-channel angular pressing (ECAP) at room temperature using a die with a channel angle of 120°. The billets showed no evidence for any surface damage after ECAP. This processing reduced the grain size from ∼23 μm in the unprocessed condition to ∼200 nm after 6 or 8 passes. It also increased the yield strength and the ultimate tensile strength and increased the elongation to failure by comparison with CP Ti processed by ECAP at an elevated temperature. The results demonstrate the advantage of processing CP Ti by ECAP at room temperature.