摘要
针对描述非晶合金在过冷液相区流动行为的虚拟应力模型虽然能定性分析应力-应变关系,但定量计算误差很大的问题,以Zr55Al10Ni5Cu30为例,采用MATLAB遗传算法优化弹性模量、最大应力和最大松弛时间,提高了模型对应力峰值及稳态应力值的计算精度;提出时间调整因子概念,可提高对应力变化历史描述的准确度;改进后的虚拟应力模型与Zr55Al10Ni5Cu30大块非晶合金单轴压缩实验的结果吻合较好。
The fictive stress model can be used to describe the stress-strain relations of bulk metallic glass in the supercooled liquid region qualitatively,but not quantitatively.In order to improve this model,take Zr55Al10Ni5Cu30 for example,the relationships of Young＇s modulus,maximum stress and maximum relaxation time with temperature and strain rate were established by using MATLAB Genetic Algorithm,so that the values of stress-overshoot and steady-state could be predicted more precisely;a time adjusting factor was also proposed to better describe the stress history.The stress-strain curves calculated by using the improved fictive stress model agree well with the experiment results of Zr55Al10Ni5Cu30 bulk metallic glass in supercooled liquid region.
出处
《塑性工程学报》
CAS
CSCD
北大核心
2012年第1期70-76,共7页
Journal of Plasticity Engineering
基金
国家自然科学基金资助项目(50821003
50835002
50975174)
高等学校博士学科点专项科研基金资助项目(20100073110044
200802480053)
关键词
锆基合金
大块非晶合金
过冷液相区
虚拟应力模型
本构模型
Zr55Al10Ni5Cu30 alloy
bulk metallic glass
supercooled liquid region
fictive stress model
constitutive model
