Abstract

The hot deformation behavior of Ti–22Al–25Nb was studied by the high temperature compression over a range of temperatures (950–1050 °C) and strain rates (0.001–10 s⁻¹) in this paper. The work-hardening (WH) and softening deformation behaviors of Ti–22Al–25Nb were analyzed. Obvious linear decreasing regimes of WH rate curves can be found before the dynamic recrystallization (DRX) onset, which indicates WH + DRV (dynamic recovery) stage. And WH rate decreased significantly with strain rate reduced and temperature elevated. A physically-based constitutive model was established, which can well predict the flow behavior of Ti–22Al–25Nb. Additional, strain-rate sensitivity coefficient distribution map was established. The higher values of m appeared at the low strain rate. When the strain rate exceeded 0.1 s⁻¹, the values of m were lower than 0.25.

Graphic Abstract

摘要

本文通过高温压缩在一定温度范围（950-1050°C）和应变速率（0.001-10 s ^-1）下研究了Ti-22Al-25Nb的热变形行为。分析了Ti-22Al-25Nb的加工硬化（WH）和软化变形行为。在动态重结晶（DRX）开始之前，可以发现WH速率曲线的明显线性下降形式，这表明WH + DRV（动态恢复）阶段。随着应变率的降低和温度的升高，WH率显着下降。建立了基于物理的本构模型，可以很好地预测Ti-22Al-25Nb的流动行为。建立了应变率灵敏度系数分布图。在较低的应变速率下出现较高的m值。当应变率超过0.1 s^-1，m的值小于0.25。

图形摘要