不连续界面相Al4C3对SiC/Al复合材料界面结合影响的第一性原理及实验

采用密度泛函理论的第一性原理及实验相结合的方法，探讨了不连续界面相Al₄C₃对SiC/Al复合材料界面结合的影响，并与无界面新相生成时进行对比。研究表明，当Al(111)表面吸附C原子时，在Bridge位置上吸附C原子最为稳定；随着C覆盖率的增加，C原子吸附能逐渐减小；当界面相呈不连续分布时，界面由原来的SiC/Al转变为(SiC+Al₄C₃)/Al，界面黏着功由原来的0.851 J/m2增加至1.231 J/m2，这主要由于当C原子在Al表面吸附时，C原子和Al原子间形成共价键和离子键，且与界面处的Si原子也形成共价键，从而促进界面结合。利用第一性原理计算的SiC/Al和(SiC+Al₄C₃)/Al体系黏着功与实验值较为接近，且变化规律相同，具有较高的参考价值。 

Effect of discontinuous interfacial phase AlC on interface bonding of SiC/Al composites:A first-principle and experiment

The effect of discontinuous interfacial phase Al₄C₃on the interface bonding of SiC/Al composites was discussed by using the first-principle approach based on density functional theory and experimental method,in comparison,the interface without new phase was also investigated.The results show that the C atom adsorbed on the surface of Al(111)is the most stable at the bridge position,and the adsorption energy of C atoms decreases gradually with the increase of C coverage.The formation of a discontinuous Al₄C₃product leads to the interface changing from SiC/Al to(SiC+Al₄C₃)/Al,and their corresponding work of interfacial adhesion increases from 0.851 J/m²to 1.231 J/m²,which is attributed to the fact that covalent bonds or ionic bonds are formed between C atoms with Al atoms when C atoms are adsorbed on the surface of Al,and covalent bonds between C atoms with Si atoms.In addition,the calculated adhesions of SiC/Al,(SiC+Al₄C₃)/Al system by first-principles are in good agreement with these of experiment,which has high reference value.