Ti-B25高强β钛合金高温变形过程本构关系的研究  

Study on Constitutive Relationship of Ti-B25High StrengthβTitanium Alloy during High Temperature Deformation

作　　者：谭伟力 刘伟[1] 戚运莲[1] 谢翀博[1] 孙花梅 TAN Wei-li;LIU Wei;QI Yun-lian;XIE Chong-bo;SUN Hua-mei(Northwest Institute for Nonferrous Metal Research,Xi'an 710016,China)

机构地区：[1]西北有色金属研究院

出　　处：《稀有金属与硬质合金》2018年第6期57-62,共6页Rare Metals and Cemented Carbides

摘　　要：在Gleeble 3800型热模拟实验机上对Ti-B25合金进行高温热压缩实验,实验条件为:温度800~1000℃,应变速率0.01~10s^-1,变形量70%。结果表明:Ti-B25合金在变形初期,随着应变的增大,流动应力迅速增大,达到峰值后,流动应力开始下降并逐渐趋于稳定,显示出稳态流动特征。在高温变形时,随着温度的升高和应变速率的减小,稳态应力和峰值应力均明显降低。通过对数据的回归处理,拟合出热变形激活能Q、结构因子A、应力指数n、应力水平参数α与应变ε之间的函数关系式,从而得到合金高温变形过程的本构方程。The thermal compression tests of Ti-B25 alloy were conducted on Gleeble 3800 thermal simulator under the conditions of 800~1000℃ temperature,0.01~10s^-1 strain rate and 70% strain.The results show that in the initial deformation stage of Ti-B25 alloy,the flow stress increases rapidly with the increase of strain.However,after reaching the peak value,the flow stress begins to decrease and gradually stabilizes, showing a steady flow characteristic.During high temperature deformation,both steady stress and peak stress decrease significantly with the increase of temperature and the decrease of strain rate.Through regression processing of the data,the functional relationships are fitted between the thermal deformation activation energy Q,the structural factor A,the stress index nor the stress level parameterαand the strainε, and then the constitutive equation of the alloy during high temperature deformation is obtained.

关 键 词：Ti-B25合金 热压缩变形 流动应力 热变形激活能 本构方程 

分 类 号：TG146.23[一般工业技术—材料科学与工程]