TC4钛合金高温变形行为及其流动应力模型  

High temperature deformation behavior of TC4 titanium alloy and its flows stress model

作　　者：罗皎[1] 李淼泉[1] 李宏[1] 于卫新[1] 

机构地区：[1]西北工业大学材料学院,西安710072

出　　处：《中国有色金属学报》2008年第8期1395-1401,共7页The Chinese Journal of Nonferrous Metals

基　　金：国家自然科学基金资助项目(50475144);西北工业大学基础研究基金资助项目(NPU-FFR-006)

摘　　要：研究变形工艺参数对TC4钛合金高温变形行为的影响。热模拟压缩实验时选取的变形温度为1093～1303K：应变速率为0．001～10．0／s；变形程度为60％。结果表明：TC4钛合金在变形开始阶段，流动应力随应变的增加迅速增加，当应变超过一定值后，流动应力开始下降并逐渐趋于稳定，出现稳态流动特征；变形温度升高和应变速率减小使TC4钛合金高温变形时的稳态应力和峰值应力显著降低；应变速率和变形温度会影响TC4钛合金进入稳态变形时变形程度的大小。利用多元回归分析建立TC4钛合金在高温变形时的流动应力模型，模型的计算值与实验数据的平均相对误差为6．25％，该模型较好地描述TC4钛合金在高温变形过程中的流动行为。The effect of processing parameters on deformation behavior of TC4 titanium alloy were investigated by using compression tests. The experiments were carried out in a Thermermaster-Z simulator at deformation temperatures of 1 093～1 303 K, strain rates of 0.001-10.0 s^-1, and height direction reduction of 60%. The results show that the flow stress of TC4 titanium alloy increases quickly with the strain and reaches a peak, then decreases to a steady value. The steady and peak stress significantly decreases with the increase of deformation temperature and decrease of strain rate, and the strain rate and the deformation temperature would also affect the critical value of strain to reach the steady flow of TC4 titanium alloy during high temperature deformation. The flow stress model of TC4 titanium alloy during high temperature deformation was established by using the regression method. The average relative difference between the calculated and experimental flow stress is 6.25%. The flow stress model can efficiently predict the deformation behavior of TC4 titanium alloy during high temperature deformation.

关 键 词：TC4钛合金 高温变形行为 流动应力模型 工艺参数 

分 类 号：TG319[金属学及工艺—金属压力加工]