Zr元素对纯铝细化机理的电子理论研究  

Electron Theory Study of the Refinement Mechanism of Zr Element on Pure Al

作　　者：李飞[1,2] 廖怡君 王旭[1] 朱庆丰[2] 崔建忠[2] LI Fei;LIAO Yijun;WANG Xu;ZHU Qingfeng;CUI Jianzhong(School of Mechanical Engineering,Liaoning Shihua University,Fushun 113001;Key Laboratory of Electromagnetic Processing of Materials,Ministry of Education,Northeastern University,Shenyang 110819)

机构地区：[1]辽宁石油化工大学机械工程学院,抚顺113001 [2]东北大学材料电磁过程研究教育部重点实验室,沈阳110819

出　　处：《材料导报》2018年第18期3190-3194,共5页Materials Reports

基　　金：国家重点基础研究发展计划项目(2012CB619506);辽宁石油化工大学国家级科研项目培育基金(2016PY-020);辽宁省博士科研启动基金(20170520008)

摘　　要：基于固体与分子经验电子理论(EET),计算了Al-Zr合金熔体中相及相界面的价电子结构,获得了表征合金性能关系的价电子结构参数统计值,并利用这些参数讨论了Zr对纯铝晶粒细化的机理。结果表明:Zr对纯铝的细化机理可以追溯到熔体中Al3Zr与α-Al相晶面间的界面共价电子密度差的统计值Δρ′,即Δρ′<10%且Δρ′值越小,合金中的异质形核效应越好,晶粒细化效果越好。Δρ′值小(2.789 04%)的Al-Al原子团簇能较容易地被异质形核核心(Al_3Zr晶体)吸附,促进异质形核及晶粒细化作用;而Δρ′值大(15.698 70%)的Al-Zr原子团簇容易从异质晶核上脱离,削弱异质形核及晶粒细化效应。Valence electron structures(VES)of the phases and the phase interfaces in the Al-Zr melt were calculated based on the empirical electron theory(EET)of solids and molecules.Meanwhile,the statistical values of VES parameters used for charactering properties of alloys were obtained,and then these parameters were used to discuss the refinement mechanism of pure Al by adding the Zr element.The results show that the refinement effect of Zr on pure Al can be related to the statistic value of the covalent electron density differenceΔρ′between interfaces of the Al 3Zr andα-Al phases.WhenΔρ′is less than 10%,with decreasing the value ofΔρ′,there is more heterogeneous nucleation,and thus the grain refinement effect is better.The Al-Al clusters with lowΔρ′(2.789 04%)value will be adsorbed by heterogeneous nuclei(Al 3Zr particles),resulting in grain refinement.However,the Al-Zr clusters with highΔρ′(15.698 70%)value are easy to separate from the nuclei,which will reduce the heterogeneous nuclei and refinement effect.

关 键 词：Zr元素 纯铝 固体与分子经验电子理论 价电子结构 细化机理 

分 类 号：TG146.2[一般工业技术—材料科学与工程] TG111.1[金属学及工艺—金属材料]