CAJ | 학술논문

本文采用第一性原理方法对清洁CuΣ5晶界与有B掺杂到间隙位的CuΣ5晶界进行了拉伸和压缩的模拟研究.结果分析表明, CuΣ5晶界结合因B的掺入得到加强.清洁CuΣ5晶界处因有较大空隙而存在电子密度低的区域,晶界结合相对较弱,在拉伸过程中晶界从其界面处开始断裂.有B掺杂在间隙位的CuΣ5晶界电子由Cu向Cu-B间积聚,晶界结合相对较强,拉伸时晶界从其近邻原子层开始断裂.在形变小于20%的压缩过程中, B的掺入未对晶界产生明显影响.
본문채용제일성원리방법대청길CuΣ5정계여유B참잡도간극위적CuΣ5정계진행료랍신화압축적모의연구.결과분석표명, CuΣ5정계결합인B적참입득도가강.청길CuΣ5정계처인유교대공극이존재전자밀도저적구역,정계결합상대교약,재랍신과정중정계종기계면처개시단렬.유B참잡재간극위적CuΣ5정계전자유Cu향Cu-B간적취,정계결합상대교강,랍신시정계종기근린원자층개시단렬.재형변소우20%적압축과정중, B적참입미대정계산생명현영향.
The uniaxial tensile and compression tests of the CuΣ5 grain boundary (GB) with and without segregated interstitial boron have been performed using first principles method based on density functional theory. Results show that boron enhances the cohesion of CuΣ5 GB and improves the mechanical property of Cu significantly. The clean boundary has lower density of valence electrons than perfect lattices and will be the point for fracture to start under sufficiently high tensile stress. The CuΣ5 GB with segregated boron has strengthened the cohesion across the boundary because of the strong B-Cu bond. Charge accumulated to Cu-B decreases slightly the strength of neighboring Cu-Cu bonds, which will be the weak point for fracture to initiate. The ultimate tensile stress is enlarged by the addition of boron. There is no significant effects occurring within 20%of the compression strain due to B-doping.