Hot deformation behavior and the processing map of Zr–1.0Be alloy in single α phase

Abstract

The hot deformation behavior, hot workability and dynamic recrystallization evolution of Zr-1.0 (wt%) Be alloy in single α phase were investigated by conducting hot compression tests. The strain rates ranging from 10 -3 s -1 to 101 s -1 and testing temperatures varying from 650 1C to 850 1C were used. Flow stress was found to increase with increasing strain rate and decrease with the increment of the deformation temperature. A constitutive equation of flow behavior was established to describe the dependence of flow stress on strain rate and deformation temperature. The activation energy for deformation of Zr-1.0Be alloy was determined to be Q ¼301 kJ/mol. The processing map of Zr-1.0Be alloy was constructed at strain rates ranging from 10 -3 s -1 to 101 s -1 and deformation temperatures varying from 650 1C to 850 1C at the true strain of 0.7. A processing map was used to identify the best domains of thermal processing, including a domain at a temperature of 650 1C and strain rate of 10 -3 s -1 , as well as another domain at deformation temperatures ranging from 800 1C to 850 1C and strain rates varying from 10 -3 s -1 to 10 -1 s -1 . Microscopic analysis of Zr-1.0Be alloy showed that the flow instability and kink were very obvious at low temperatures and high strain rates. At high temperatures and low strain rates, the dynamic recrystallization became the main softening mechanism during hot working.

High-cycle fatigue behaviour and mechanism analysis of a forged TiZr-based alloy

“…In recent years, studies on TiZr-based alloys have focused on optimisation of the chemical composition, microstructure and mechanical property of alloys through different processing and heat treatments. [4][5][6] Tan et al 7,8 have investigated the hot deformation behaviour of alloys.…”