The low strain rate response of as-cast Ti-6Al-4V alloy with an initial coarse lamellar structure

Abstract

The microstructure and microtexture evolution of the as-cast Ti-6Al-4V alloy with an initial lamellar microstructure was investigated in the temperature range of 900–1050◦C and the low strain rate range of 10−3–10−1 s−1. In the ranges 900–950◦C and 10−3–10−2 s−1, globularization of the α lamellar structure took place; the initial α {0001} texture softened, and the {0001} texture rotated to the transverse direction. Additionally, the increasing strain rate led to more randomization. The globularization process was considered to be continuous dynamic recrystallization (CDRX). At strain rates higher than 10−2 s−1 and temperatures between 900 and 950◦C, flow instabilities occurred. In the β range, dynamic recrystallization (DRX) occurred at a temperature of 1050◦C and a strain rate of 10−3 s−1.