Al-Cu-Mg合金S相及S/α相界面价电子结构分析  

Valence Electron Structures Analysis of S Phase and the S/αInterface in Al-Cu-Mg Alloy

作　　者：屈华[1] 徐巧至 刘伟东[2] 齐健学 Qu Hua;Xu Qiaozhi;Liu Weidong;Qi Jianxue(Liaoning University of Technology,Jinzhou 121001,China)

机构地区：[1]辽宁工业大学材料科学与工程学院,辽宁锦州121001 [2]辽宁工业大学,辽宁锦州121001

出　　处：《稀有金属材料与工程》2020年第11期3816-3821,共6页Rare Metal Materials and Engineering

基　　金：辽宁省科学技术计划项目(SY2016008)。

摘　　要：基于EET理论,计算了α-Al与S相及S/α相界面的价电子结构,分析了S相价电子结构与析出强化、S/α相界面价电子结构与界面性能的关系。研究表明:S相共价键分布较为均匀,Cu原子将S相原子间键合力最强的4条共价键连接在一起构成主键络。S相析出强化的微观本质在于其最强共价键的键合力比基体α-Al的大135.14%,对位错运动具有较强的阻力作用。S相与基体α-Al形成的(100)S//(100)α和(010)S//(0■2)α及(001)S//(021)α面的共价电子密度差?ρ分别为0.003%、3.564%和5.811%,(100)S//(100)α面上的共价电子密度为10.3915和10.3918nm-2,(010)S//(0■2)α面上的共价电子密度为0.0486和0.0469 nm-2,(001)S//(021)α面上的共价电子密度为0.0486和0.0459 nm-2。与(001)S//(021)α和(010)S//(0■2)α面相比,(100)S//(100)α面的原子键合力与共价电子密度均最大,共价电子密度差最小,界面连续性最好,界面的应力最小。Based on the empirical electron theory of solids and molecules,the valence electron structures(VESs)of S phase and the S/αinterface were calculated;then the relationships between their VESs and precipitation strengthening and interface properties were analyzed in Al-Cu-Mg alloys.It is shown the covalent bond distribution of S phase is uniform and its main bond network is built by four stronger covalent bonds connected by Cu atoms.The nature of precipitation strengthening of S phase lies in its binding force of the strongest covalent bond which is 135.14%bigger than that of the matrixα-Al and causes the stronger inhibition to the dislocation movement.The covalent electron density difference of(100)S//(100)α,(010)S//(0■2)αand(001)S//(021)αis 0.003%,3.564%and 5.811%,respectively,while the covalent electron density of(100)S//(100)αis 10.3915 and 10.3918 nm-2,and that of(010)S//(0■2)αis 0.0486 and 0.0469 nm-2,and that of(001)S//(021)αis 0.0486 and 0.0459 nm-2.Compared with(001)S//(021)αand(010)S//(0■2)α,the binding force and covalent electron density of(100)S//(100)αare the biggest while its covalent electron density difference is the smallest,so that the interface continuity is the best and the interface stress is the smallest.

关 键 词：AL-CU-MG合金 S相 相界面 价电子结构 电子密度差 

分 类 号：TG111.1[金属学及工艺—物理冶金]