Mg-Si合金系B81-型合金基因浓度及性质的研究  

Research on properties and concentrations of alloy genes of B81-type of Mg-Si alloy system with HCP structure

作　　者：彭红建[1,2] 刘劲远 李小波[2] 聂耀庄[2] 罗宾辉 谢佑卿[2] PENG Hongjian;LIU Jinyuan;LI Xiaobo;NIE Yaozhuang;LUO Binghui;XIE Youqing(School of Chemistry and Chemical Engineering,Central South University,Changsha 410083,China;School of Materials Science and Engineering,Central South University,Changsha 410083,China)

机构地区：[1]中南大学化学化工学院,湖南长沙410083 [2]中南大学材料科学与工程学院,湖南长沙410083

出　　处：《中南大学学报（自然科学版）》2023年第7期2576-2583,共8页Journal of Central South University:Science and Technology

基　　金：湖南省重大科技专项(2020GK2100)。

摘　　要：以Mg-Si合金系为例,根据合金基因理论和中心配位原子模型,推导密排六方(HCP)结构B8_(1)-型合金基因浓度的表达式。计算B8_(1)-型有序合金的基因浓度随Si的原子数分数(xSi)和有序度(σ)的变化,阐明B8_(1)-型有序合金的基因浓度随xSi和σ的变化特征。计算B8_(1)-型有序合金和无序Mg((1-x))Six合金随xSi的变化特征。研究结果表明:与无序合金相比,B8_(1)-型有序合金的参数如结合能等变化更大,因此,有序化可提高Mg-Si合金的抗压强度;s和p轨道上的共价电子数(分别为ns和np)随Si的原子数分数的增加而增多,当xSi>0.4时反而减少;共价电子数增多有利于提高Mg-Si合金的抗腐蚀强度,这为智能化制备高强轻质Mg合金指明了方向。Taking Mg-Si alloy system as an example,the formula of concentration of alloy genes in HCP system were obtained on the basis of the theory of alloy gene and the model of central coordination atoms.The gene concentrations of B8_(1)-type ordered alloys was calculated as functions of composition xSi and ordering degree(σ).The changing characteristics of the gene concentrations of B8_(1)-type ordered alloys was interpreted.The properties of B8_(1)-type ordered alloys and disordered Mg(1-x)Six alloys were calculated as a function of xSi.The results show that variations of properties of B8_(1)-type ordered alloys is greater than those of disordered Mg(1-x)Six alloys,such as cohesive energy,etc,so the ordering degree can enhance the compressive strength of Mg-Si alloys.The number of covalent electrons,such as ns and np,increases as functions of composition xSi at first,and then decreases as xSi>0.4.The increase of the number of covalent electrons ns and np is benefited for the anti-corrosion resistance.Therefore,theoretical instructions can be supplied in intelligent production of new generation high strength and light Mg-Si alloy.

关 键 词：Mg-Si合金系 HCP结构 基因浓度 

分 类 号：TG155[金属学及工艺—热处理]