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采用第一性原理赝势平面波的方法研究Ni(001)、Ni3Nb(001)表面和Ni/Ni3Nb(001)界面。计算界面终端为Ni或Ni+Nb,堆积方式为顶部位置或空心位置这4种界面模型的粘附功、稳定性及电子结构。结果表明:Ni(001)和Ni3Nb(001)表面具有8个原子层时展现出较好的体相似性;以Ni+Nb为界面终端,堆积方式为空心位置的界面模型具有最大的结合强度和临界裂纹扩展应力,且具有最好的热稳定性。该模型界面处的Ni原子和Nb原子之间是共价键,这主要是由Nb 4d和Ni 3d轨道的电子贡献的。比较Ni/Ni3Nb(001)界面和Ni/Ni3Al(001)界面的性质可知,前者的热稳定性比后者的差,且更难形成界面,但是Ni/Ni3Nb(001)界面的形成能改善镍基合金的力学性能。
The Ni (001), Ni3Nb (001) and Ni / Ni3Nb (001) interfaces were investigated by the first principle pseudopotential plane wave method. The calculation of the adhesion interface, the stability and the electronic structure of the four interface models with Ni or Ni + Nb as the terminal and the stacking mode as the top or the hollow position. The results show that the Ni (001) and Ni3Nb (001) surfaces exhibit good bulk similarity when they have 8 atomic layers. The Ni / Nb interfacial interface has the highest bond strength and Critical crack growth stress, and has the best thermal stability. The Ni atom and the Nb atom at the model interface are covalent bonds, which are mainly contributed by the electrons of Nb 4d and Ni 3d orbitals. Comparing the properties of the Ni / Ni3Nb (001) interface and the Ni / Ni3Al (001) interface, the thermal stability of the former is worse than that of the latter, and it is more difficult to form an interface. However, the Ni / Ni3Nb Mechanical properties of base alloys.