Investigating the hot deformation behavior and microstructural evolution of Mo-14Re alloy at various strains and strain rates

Abstract

This study examines the hot deformation behavior of Mo-14Re alloy at various true strains (15%, 35%, 65%) and strain rates (0.01 s⁻¹, 10 s⁻¹) at a temperature of 1400K. The findings indicate that dynamic recovery (DRV) and dynamic recrystallization (DRX) occur concomitantly as strain increases at a low strain rate of 0.01 s⁻¹, with DRV being the predominant softening mechanism. At a strain of 65%, DRX emerges as the primary softening process. Conversely, under high strain rates of 10 s⁻¹, DRX is inhibited, and the Mo-14Re alloy experiences work hardening due to an increase in dislocation density. Microscopic analysis shows that the high-density dislocations facilitate the continued nucleation and growth of recrystallized grains at low strain rates. At high strain rates, tangled dislocations hinder dislocation motion and recrystallization. Regarding texture evolution, stronger {100}//CD and weaker {111}//CD fiber texture is observed at low strain rates of 0.01 s⁻¹, while stronger {111}//CD and weaker {100}//CD fiber texture forms at high strain rates of 10 s⁻¹, with enhanced texture intensity. Mechanistic analysis confirms the activation of the {110}<111>, {112}<111>, and {123}<111> dislocation slip systems at elevated temperatures, with the {123}<111> system being the most dominant.