基于内变量的Ti555211合金热变形本构模型  

Constitutive Modeling of Near Beta Titanium Alloy Ti555211 Based on the Internal-State-Variable Method during Hot Deformation Process

作　　者：安震[1] 冯勇[1,2] 李金山[1] 刘向宏[2] 杜予晅[2] 楼美琪 刘广发[1,2] 韩逢博[1] 

机构地区：[1]西北工业大学凝固技术国家重点实验室,陕西西安710072 [2]西部超导材料科技股份有限公司,陕西西安710018

出　　处：《稀有金属材料与工程》2014年第8期1902-1907,共6页Rare Metal Materials and Engineering

基　　金：国家自然科学基金资助(51171150);凝固技术国家重点实验室自主研发课题(62-TP-2011)

摘　　要：利用Gleeble-3800热模拟实验机,在应变速率在0.001~1 s-1以及变形温度在750~950℃范围内对Ti555211合金进行等温恒应变速率压缩实验。本工作基于位错变化密度的内变量方法建立了Ti555211合金热变形本构模型,通过真应力-真应变曲线分析了变形温度和变形速率对流变应力和微观组织的影响规律。结果表明：所建立的本构模型与实验值的平均相对误差为15.25%,相关系数为0.94277,从而为制定新型Ti555211近β钛合金锻造工艺提供科学的理论依据。Isothermal compression tests of Ti555211 titanium alloy has been conducted on a Gleebe-3800 hot-simulator at the strain rate ranging from 0.001 to 1 s-1 and the deformation temperature ranging from 750 to 950 ℃. A constitutive model using dislocation density rate as an internal state variable has been proposed for hot working of Ti555211 titanium alloy. According to the isothermal compression test curves, the influence of deformation temperature and stain rate on stress has been investigated. The results show that the correlation coefficient （R） and the average absolute relative error （AARE） for the constitutive model using dislocation density rate as an internal state variable are found to be 0.94277 and 15.25%, respectively, which provide a guide for process optimization and control of near β deformation of Ti555211 titanium alloy.

关 键 词：Ti555211合金 本构关系 近Β钛合金 

分 类 号：TG146.23[一般工业技术—材料科学与工程]