摘要
利用ETM105D型拉伸实验机对Al-Cu-Mg-Sc合金进行单轴热拉伸实验。研究了变形温度为250~450℃和应变速率为10-4~10-1s-1下Al-Cu-Mg-Sc合金的高温流变变形行为。采用Zener-Hollomon参数法构建该合金的高温流变本构关系。结果表明:该合金的真应力-真应变曲线不是典型的动态回复曲线,在很小的应变下达到峰值应力,之后流动应力先缓慢下降后明显下降,直至断裂,其中由于软化现象存在一个应力减少量。通过线性拟合计算Al-Cu-Mg-Sc合金的结构因子A=3.085×1018s-1,应力指数n=4.75325及变形激活能Q=257.4 k J/mol,获得其在高温拉伸条件下用Z参数表达的流变应力本构方程。
The uniaxial hot tensile experiment of Al-Cu-M-Sc alloy was carried out by using ETM105D tensile testing machine.The elevated temperature flow deformation behavior of Al-Cu-Mg-Sc alloys sheet were studied by tensile deformation at 250-450℃and high temperature deformation at strain rate of 10-4-10-1s-1with ETM105D simulated machine.The Zener-Hollomon parameter method was used to construct the high temperature rheological constitutive relationship of the alloy.The results show that the true stress-true strain curve is not a typical dynamic recovery curve,and the peak stress reaches under a small strain.Then,the flow stress first slowly decreases then obviously decreases until the fracture,and there is a stress reduction due to the softening phenomenon.The structural factor A=3.085×1018s-1and the stress index n=4.75325 and the deformation activation energy Q=257.4 k J/mol of Al-Cu-Mg-Sc alloy were calculated by linear fitting.The constitutive equation of the flow stress expressed by Z parameter of the alloy at elevated temperature is obtained.
作者
李旺珍
孙有平
何江美
胡一杰
LI Wangzhen;SUN Youping;HE Jiangmei;HU Yijie(School of Mechanical and Transportation Engineering,Guangxi University of Science and Technology,Liuzhou 545006,China)
出处
《热加工工艺》
北大核心
2020年第14期58-61,65,共5页
Hot Working Technology
基金
国家自然科学基金项目(51864006)
广西自然科学基金项目(2016GXNSFDA380008,2018GXNSFBA281195)
柳州市科学研究与技术开发计划项目(2017BD20301)
2019年广西研究生教育创新计划项目(YCSW2019205)。
