Synthesis, Microstructure, and Property of Cr2AlC

Cr2AlC is an unusual layered ternary ceramic that combines the merits of both metals and ceramics. The salient properties of Cr2AlC are strongly related to its bonding characteristics and microstructures. Synthesis,microstructure, and property of Cr2AlC are reviewed in this paper. First, theoretical calculations and physical properties are introduced. Then, the processing of Cr2AlC ceramic in both bulk form and thin films and their basic mechanical properties are summarized. Atomic-scale characterizations of Cr2AlC, as well as the microstructural relationships among Cr2AlC, Al8Cr5, and AlCr2 were achieved using a series of transmission electron microscopy (TEM) techniques. Moreover, high-temperature oxidation and hot corrosion behaviors of Cr2AlC were investigated by means of thermogravimetric analysis, X-ray diffraction, Raman spectroscopy,scanning electron microscopy, and TEM. Mechanism of the excellent high-temperature corrosion resistance of Cr2AlC is discussed based on systematic microstructural analyses. Finally, concise conclusions are drawn.