Deformed Microstructures and Mechanical Properties of CP-Ti Processed by Multi-Pass ECAP at Room Temperature

Abstract

The deformed microstructures and mechanical properties of commercial pure titanium (CP-Ti) with an initial grain size of about 28 μm was investigated using equal channel angular pressing (ECAP). ECAP was conducted at room temperature adopting a die with a channel angle of 120° via route BC. Special attention was paid on the microstructure evolution and mechanical properties of the ECAP samples. Deformation twins were found in most grains after the first and second pass of ECAP. After four ECAP passes, the original grains were refined from 28 μm to about 250 nm, and the ultimate strength and microhardness were significantly enhanced to 773 MPa and 2486 MPa, respectively. Meanwhile good ductility of 16.8% elongation still remained.