The Interaction Of Carbon-vacancy In NiAl

B2-NiAl has lots of good characteristic which is regarded as the new high-temperature material and satisfies with the requirements of the aerospace industry materials. At the low temperature, it is very poor for plasticity and has poor toughness. The low strength feature will show up at the high temperature. All these defects limit the NiAl into practical use. The little quantity of impurity has a great influence on the performance of NiAl. The vacancy as a default in NiAl also had an influence on its characteristic. As the impurity and vacancy exist in NiAl at the same time, the interaction of them must have the influence on NiAl. The research method is the first principle and calculation which is used to find out the interaction of the impurity and vacancy.The vacancy can catch the carbon in the situation of vacancy Ni and vacancy Al. In the situation of vacancy Ni, the single carbon can stay at one of the six Ni octahedron sites near the vacancy. The same result happens in the situation of vacancy Al. So the single carbon exists at the octahedron sites near the vacancy both in the situation of Ni and Al. After the analysis of the structure and electrical density of the NiAl, the stable position has a positive effect on the interaction of carbon and vacancy and it also improves the combination of C and the near atoms. The C leaves the center of vacancy and becomes the C1 V clusters.The research of multiple arrest C shows that the C prefers to enter the NiAl by the way Sequential. In the situation of vacancy Ni, the vacancy can arrest 4 C at most. And 5 C can be arrested in the situation of vacancy Al. The vacancy exists by the form CnV clusters. The combination between C-C can be shown clearly through the electrical density figure and DOS figure.The research of the density and temperature effect shows that the concentration of the pure vacancy increase with the temperature. Most of the impurity C have been arrested by the vacancy and existed as CnV clusters. When the temperature increase, the kinetic energy of the C increase at the same time which will cause the C gets out of the arrest of vacancy. So the concentration of the Cn V clusters.will descrease.