The high temperature deformation behavior and microstructure of TC21 titanium alloy

TC21 titanium alloy was hot compressed isothermally at temperatures ranging from 880 degrees C to 950 degrees C and strain rates ranging from 0.01 to 10 s(-1). Microstructures were investigated by electron backscatter diffraction (EBSD) technique and transmission electron microscopy (TEM), and processing maps were developed at different strains. It is found that strain rate is a key factor for the formation of hot deformation microstructure. The stress-strain curves were exhibited flow softening behavior at high strain rate above 1 s(-1), while equiaxed grains were found at lower strain rates. There is no large instability zone besides two peak-areas of 880-900 degrees C, 1-10 s(-1) and 925-950 degrees C, 10(-0.5) to 10 s(-1). (C) 2010 Elsevier B.V. All rights reserved.