挤压态Mg-6Zn-0.8Zr-0.5Y镁合金热变形行为研究  

Thermal deformation behavior of extruded Mg-6Zn-0.8Zr-0.5Y magnesium alloy

作　　者：徐永东[1] 付玉 王洪海[2] 罗妮娜[2] 王荫洋 宋运坤[1] 刘辰[1] XU Yongdong;FU Yu;WANG Honghai;LUO Nina;WANG Yinyang;SONG Yunkun;LIU Chen(Ningbo Branch of Chinese Academy of Ordnance Science,Ningbo 315103,China;Xi′an Modern Chemistry Research Institute,Xi′an 710065,China)

机构地区：[1]中国兵器科学研究院宁波分院,浙江宁波315103 [2]西安近代化学研究所,陕西西安710065

出　　处：《兵器材料科学与工程》2023年第2期47-54,共8页Ordnance Material Science and Engineering

基　　金：宁波市科技创新2025重大专项(2020Z060);宁波市自然科学基金(202003N4340)。

摘　　要：通过研究挤压态Mg-6Zn-0.8Zr-0.5Y镁合金在300、350、400℃,0.001、0.01、0.1、1 s^(-1)应变率下的压缩变形行为,获得挤压态Mg-6Zn-0.8Zr-0.5Y镁合金热压缩过程的流变应力-应变曲线,构建基于Arrhenius方程的本构模型和热加工图,阐明变形温度和应变率对挤压态Mg-6Zn-0.8Zr-0.5Y镁合金显微组织的影响规律。结果表明:挤压态Mg-6Zn-0.8Zr-0.5Y镁合金热压缩过程的变形激活能Q为118.73 kJ/mol,应力指数n为4.480 9,安全热加工区域为300~400℃、0.426~2.718 s^(-1)。通过热变形组织分析可知,当变形条件为350℃、0.1 s^(-1)时,组织为细小均匀的动态再结晶组织,能改善塑性成形能力,热加工性较好,为挤压态Mg-6Zn-0.8Zr-0.5Y镁合金热加工工艺的制定提供指导。The heat deformation behavior of the extruded Mg-6Zn-0.8Zr-0.5Y magnesium alloy at deformation temperatures of300 ℃,350 ℃ and 400 ℃,strain rates of 0.001 s^(-1),0.01 s^(-1),0.1 s^(-1)and 1 s^(-1)was studied. And the flow stress-strain curve of extruded Mg-6Zn-0.8Zr-0.5Y magnesium alloy during hot compression was obtained. The constitutive equation and thermal processing map based on the Arrhenius equation were constructed. The effect of deformation temperature and strain rate on the microstructure of extruded Mg-6Zn-0.8Zr-0.5Y magnesium alloy was clarified. The results show that the deformation activation energy Q of the extruded Mg-6Zn-0.8Zr-0.5Y magnesium alloy is 118.73 kJ/mol,the stress exponent n is 4.480 9. Besides,the suitable hot working area are 300 ℃-400 ℃ and 0.426 s^(-1)-2.718 s^(-1). It can be seen from the microstructure evolution that when the deformation conditions are 350 ℃ and 0.1 s^(-1),the dynamic recrystallization microstructure is fine and uniformly distributed.Which improve plastic forming ability and show good hot workability. This study provides guidance for the formulation of hot working technology of extruded Mg-6Zn-0.8Zr-0.5Y magnesium alloy.

关 键 词：镁合金 热变形 本构方程 热加工图 动态再结晶 

分 类 号：TG146.2[一般工业技术—材料科学与工程]