应变对β-CEZ钛合金热加工图的影响研究

Study of Effect of Strain on the Processing Map of β-CEZ Titanium Alloy

基于β-CEZ钛合金的热模拟压缩实验,以动态材料模型为基础,建立了不同应变下的β-CEZ钛合金热加工图。从能量耗散率、非稳定参数和非稳定变形区三个方面分析了应变对β-CEZ钛合金热加工图的影响规律。分析结果表明：随着应变的增大,β-CEZ钛合金能量耗散率对应的等值线越来越密集,高能量耗散率对应的区域逐渐减小,而非稳定变形区越来越大,由小应变时的两个非稳定变形区变为大应变时贯穿整个温度范围的一个大非稳定变形区;不同应变下,应变速率为0.01~0.018 s-1、变形温度为820~920℃时,能量耗散率都大于0.45且没有发生塑性失稳,该范围内的工艺参数最适合β-CEZ钛合金的锻造。

The processing maps of β-CEZ titanium alloy have been established based on the Dynamic Materials Model （DMM） and isothermal compression experiment. In this paper, the effect of strain on the processing map is investigated from the aspects of power dissipation efficiency, unstable parameter and unstable deformation region. The results show that the contour of efficiency of power dissipation becomes more and more intensive, and the region responding to the high value of efficiency of power dissipation decreases with the increasing of strain. Meanwhile, the unstable region increases and becomes to a large region throughout the whole deformation temperature range at the higher strain. Under different strains, the values of efficiency of power dissipation are greater than 0. 45 without unstable flow at the strain rates of 0.01 -0. 018 s^-1 , and the deformation temperatures of 820 -920 ℃. They are the most suitable processing parameters for β-CEZ titanium alloy forging.