First-principles investigation on stability and electronic structure of Sc-dopedθ′/Al interface in Al−Cu alloys  

Al-Cu合金中Sc掺杂θ′/Al界面稳定性和电子结构的第一性原理研究

作　　者：Dong-lan ZHANG Jiong WANG Yi KONG You ZOU Yong DU 张冬兰;汪炯;孔毅;邹有;杜勇(中南大学粉末冶金研究院,长沙410083;中南大学信息与网络中心,长沙410083)

机构地区：[1]Powder Metallurgy Research Institute,Central South University,Changsha 410083,China [2]Information and Network Center,Central South University,Changsha 410083,China

出　　处：《Transactions of Nonferrous Metals Society of China》2021年第11期3342-3355,共14页中国有色金属学报（英文版）

基　　金：the financia supports from the National Key Research and Development Program of China (No. 2019YFB2006500);the National Natura Science Foundation of China (Nos. 52171024 51771234, 51601228)。

摘　　要：The properties of Sc-dopedθ′(Al_(2)Cu)/Al interface in Al−Cu alloys were investigated by first-principles calculations.Sc-doped semi-coherent and coherentθ′(Al_(2)Cu)/Al interfaces(Sc doped in Al slab(S1 site),Sc doped inθ′slab(S2 site))were modeled based on calculated results and reported experiments.Through the analysis of interfacial bonding strength,it is revealed that the doping of Sc at S1 site can significantly decrease the interface energy and increase the work of adhesion.In particular,the doped coherent interface with Sc at S1 site which is occupied by interstitial Cu atoms has very good bonding strength.The electronic structure shows the strong Al—Cu bonds at the interfaces with Sc at S1 site,and the Al—Al bonds at the interfaces with Sc at S2 site are formed.The formation of strong Al—Cu and Al—Al bonds plays an important role in the enhancement of doped interface strength.通过第一性原理计算方法研究Al-Cu合金中Sc掺杂θ′(Al_(2)Cu)/Al的界面特性。根据计算结果和已报道的实验结果,建立Sc掺杂的半共格和共格θ′(Al_(2)Cu)/Al界面(Sc掺杂在Al表面(S1位点),Sc掺杂在θ′表面(S2位点))模型。通过对界面结合强度的分析,发现Sc位于S1位点时,掺杂界面的界面能显著降低,黏附功显著增加。特别是被间隙Cu原子占据的共格界面,当Sc位于S1位点时具有极好的结合强度。电子结构表明,Sc在S1位点的界面形成强Al—Cu键,而Sc在S2位点的界面形成Al—Al键。Al—Cu和Al—Al键的形成对提高掺杂界面强度起着至关重要的作用。

关 键 词：Al−Cu alloys Sc-dopedθ′/Al interface interfacial bonding strength electronic structure 

分 类 号：TG146.21[一般工业技术—材料科学与工程]