(1. 中南大学 材料科学与工程学院，长沙 410083；
2. 中南大学 有色金属材料教育部重点实验室，长沙 410083)
摘 要: 基于第一性原理方法，研究温度、原子化学配比、Al 活度、O活度和杂质偏聚对内氧化Cu/Al2O3界面的影响作用。计算得到的界面相图及相应能量学结果表明：界面平衡相结构随制备气氛的变化而变化；富O相界面的结合强度最高，富Al相界面的结合强度其次，它们均约3倍于理想化学配比相界面的结合强度；杂质S对界面的危害性明显，对富Al相和理想配比相界面具有强烈的偏聚能力，且严重削弱界面强度(约可达65%)，并降低氧化铝颗粒尺寸的稳定性，但S不能向富O 相界面偏聚；相较于S，另一种杂质P向富Al相和理想配比相界面的偏聚能力不强，偏聚后对界面的危害性也较S弱。但P能向富O相界面偏聚，使界面强度严重降低。
关键字: Cu/Al2O3界面；内氧化；结合强度；杂质偏聚；第一性原理
（1. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
2. Key Laboratory of Nonferrous Metal Materials, Ministry of Education, Central South University, Changsha 410083, China）
Abstract:Based on the first-principles study, the effects of temperature, interfacial stoichiometry, Al activity, O activity and impurity segregation on the internally oxidized Cu/Al2O3 interface were studied. The calculated interfacial phase diagrams and corresponding energetics suggest that, the equilibrium interface structure varies with the ambient; the O-rich type interface, followed by the Al-rich type, has significantly stronger adhesion than its stoichiometric counterpart. Impurity S strongly segregates to Al-rich and stoichiometric type interfaces, degrades the adhesion (up to about 65%) and also reduces the size stability of alumina particles in Cu, while the O-rich interface is immunized from S segregation. P, as another common impurity in Cu, has a limited capability to segregate to the Al-rich and the stoichiometric interfaces, but it can segregate to the O-rich interface and reduce the adhesion seriously.
Key words: Cu/Al2O3 interface; internal oxidation; adhesion strength; impurity segregation; first principles
