Ti-B25合金高温变形时的塑性流动软化行为  

Plastic Flow Softening Behavior of Ti-B25 Alloy During High Temperature Deformation

作　　者：孙花梅 刘伟[1] 戚运莲[1] 李修雷 南榕 Sun Huamei;Liu Wei;Qi Yunlian;Li Xiulei;Nan Rong(Northwest Institute for Nonferrous Metal Research,Xi’an 710016,China)

机构地区：[1]西北有色金属研究院,陕西西安710016

出　　处：《钛工业进展》2022年第1期6-11,共6页Titanium Industry Progress

摘　　要：通过热模拟压缩实验,研究了变形温度、应变速率对Ti-B25合金高温变形时流动应力和峰值流动应力的影响,并结合组织演变规律揭示了其高温塑性流动软化机理。结果表明:流动应力和峰值流动应力均随变形温度的下降以及应变速率的增大而增大。应变速率为10.0 s^(-1)时,随着变形温度的升高,流动软化程度减小,并且α+β两相区的软化程度远高于β单相区的软化程度。应变速率对Ti-B25合金温升影响最大,变形温度次之。当应变速率为10.0 s^(-1)时,Ti-B25合金的温升最高,流动软化程度也明显高于其他应变速率下的流动软化,这与该应变速率下Ti-B25合金发生局部塑性流动有关。当应变速率为0.01 s^(-1)时,Ti-B25合金的温升较小,但仍存在流动软化现象,这是因为该应变速率条件下材料发生了动态再结晶。The effect of deformation temperature and strain rate on flow stress and peak flow stress of Ti-B25 alloy were investigated through hot compression tests.And the high temperature softening mechanism was revealed based on microstructure evolution.The results show that both the flow stress and peak flow stress increase with the decreasing of deformation temperature and increasing of strain rate.When the strain rate is 10.0 s^(-1),the flow softening extent decreases with the increasing of deformation temperature,and the softening extent inα+βphase region is much higher than that inβphase region.The strain rate has a greater effect than the deformation temperature on the temperature rise.When the strain rate is 10.0 s^(-1),the temperature rise of Ti-B25 alloy is the highest,and the flow softening extent is also significantly higher than those at other strain rates due to the local plastic flow.When the strain rate is 0.01 s^(-1),the temperature rise is very small,but the flow softening also occurs due to the dynamic recrystallization.

关 键 词：Ti-B25合金 热压缩 流动应力 峰值流动应力 流动软化 

分 类 号：TG146.23[一般工业技术—材料科学与工程]