金属间化合物CuBe和CuBe_(2)的力学和电子结构性质研究  

Mechanical and electronic structural properties of intermetallic compounds CuBe and CuBe_(2)

作　　者：陈雨轩 殷蕊 陈磊 张美光 CHEN Yu-xuan;YIN Rui;CHEN Lei;ZHANG Mei-guang(Institute of Physics and Optoelectronic Technology,Baoji University of Arts and Sciences,Baoji 721016,Shaanxi,China)

机构地区：[1]宝鸡文理学院物理与光电技术学院,陕西宝鸡721016

出　　处：《宝鸡文理学院学报（自然科学版）》2024年第2期20-27,共8页Journal of Baoji University of Arts and Sciences(Natural Science Edition)

基　　金：陕西省自然科学基金项目(2023-JC-YB-021;2024JC-YBMS-048);宝鸡文理学院校级大学生创新创业训练项目(2023XJ108)。

摘　　要：目的 探究金属间化合物CuBe和CuBe_(2)的弹性力学行为和电子结构特征,以期对Cu-Be二元合金的力学强化机制有直观和深刻的理解。方法 采用基于密度泛函理论的第一性原理和基于“应变-应力”的计算方法。结果 CuBe和CuBe_(2)晶格参数的理论计算值与实验结果一致,单晶弹性常数结果表明这2种材料均满足弹性力学稳定判据;由Be-Be强共价键构成的Be三棱锥是CuBe_(2)具有优异力学性能的主要原因;CuBe和CuBe_(2)这2种金属间化合物中同时存在金属键、离子键和共价键的复杂成键特征。结论 Be原子含量的增加可以有效提升Cu-Be合金中金属间化合物的拉伸和剪切强度,但是会减弱合金的韧性和延展性。Purposes—To provide an intuitive and profound understanding of the mechanical strengthening mechanism of Cu-Be binary alloys by fully investigating the mechanical behavior and electronic structure characteristics of intermetallic compounds CuBe and CuBe_(2).Methods—First-principles of density functional theory(DFT)and the“strain-stress”methods were employed in the investigation.Results—The calculated lattice parameters of CuBe and CuBe_(2) are in agreement with available experimental data.The obtained crystal elastic constants showed that both intermetallics meet the cubic elastic stability criterion.The excellent mechanical properties of CuBe_(2) was mainly attributed to the Be tripyramids composed of strong Be-Be covalent bonds.The obtained findings further reveal that both CuBe and CuBe_(2) intermetallics possess a complex bonding characteristics including metallic,ionic and covalent bonds.Conclusions—The increase in Be content can effectively improve the tensile and shear strengths of such two intermetallics,but it will weaken the toughness and ductility of the alloy.

关 键 词：金属间化合物 第一性原理计算 力学性质 电子结构 

分 类 号：O469[理学—凝聚态物理]