摘要
在Gleeble-3500热/力模拟试验机上对轧态Ni-40Ti形状记忆合金进行等温恒应变速率拉伸试验,研究了变形温度为650~850℃,应变速率为0.01~1.00s^(-1)条件下合金的热变形行为。结果表明,应变速率和变形温度对流变应力具有显著影响,合金流变应力随着变形温度升高和应变速率降低而降低。基于Arrhenius方程和多元线性回归法构建了合金本构关系模型。误差分析表明,采用Arrhenius方程预测轧态Ni-40Ti合金的热拉伸变形行为存在较大误差;而采用多元线性回归法建立的本构模型能较准确预测轧态Ni-40Ti合金的热拉伸变形行为,流变应力预测值与试验值符合较好。
The hot deformation behavior of as-rolled Ni-40 Ti shape memory alloy was investigated by the Gleeble-3500 thermal simulation machine at deformation temperature in range of 650 ℃ to 850 ℃ and strain rate in range of 0.01s^-1 to 1.00s^-1.The results show that the flow stress of Ni-40 Ti shape memory alloy is affected greatly by strain rate and deformation temperature,and the flow stress is decreased with the increase of deformation temperature and the decrease of strain rate.The hot deformation constitutive relationship is established based on the Arrhenius equation and multivariate linear regression equation,respectively.The error analysis shows that there exists large error between the value of experiment stress and calculated one by the Arrhenius equation.Therefore,the multivariate linear regression constitutive model is more appropriate for the prediction of flow stress of Ni-40 Ti shape memory alloy,whose average relative error is very small.
出处
《特种铸造及有色合金》
CAS
CSCD
北大核心
2016年第4期425-429,共5页
Special Casting & Nonferrous Alloys
基金
国家自然科学基金资助项目(51164030)
江西省自然科学基金资助项目(20122BAB216018)
江西省教育厅科技项目(GJJ150703)
关键词
Ni-40Ti合金
热拉伸变形
本构关系
Ni-40Ti Shape Memory Alloy
Hot Tensile Deformation
Constitutive Relationship
