Formation of alumina reinforced Al-Ni intermetallic-based matrix composite by displacement reaction

摘要

Al-Ni intermetallics are popular materials for high temperature operations and coating applications. Recently, there are considerable interests in reinforcing Al-Ni intermetallics with alumina or toughing alumina with Al-Ni mtermetallics. These works usually involve two common types of Al-Ni intermetallics, namely AlNi_3 and AlNi due to their excellent properties on high temperatures. However, in the needs of lightweight materials, the applications of those intermetallics are restricted by their high densities. In our work, we have developed a relatively lightweight alumina reinforced Al-Ni intermetallic-based matrix composite by using the displacement reaction between Al and NiO. The in-situ formed Al_3Ni_2 that has a lower density is being used as the matrix in the composite.