Solid-liquid reaction synthesis and simultaneous densification of polycrystalline Ti2AlC

A novel solid-liquid reaction synthesis and simultaneous densification process was developed to fabricate Ti2AlC material using the stoichiometric mixture of Ti, Al and graphite powders as starting materials. This method is a one-step process for the preparation of dense poycrystalline Ti2AlC. Moreover, it provides the advantages of low synthesis temperature, short reaction time and simultaneous synthesis and densification. The microstructure evolution during the high temperature processing was described and the properties of polycrystalline Ti2AlC prepared by this method at 1400 degreesC were investigated. The results showed that Ti2AlC exhibited metallic electrical conductivity and high mechanical properties. The electrical conductivity of Ti2AlC at room temperature was 4.42 x 10(6) Omega(-1) (.) m(-1) and increased with decreasing temperature. The Vickers hardness of Ti2AlC was 2.8 GPa. No indentation cracks were observed and the microdamage is confined in the immediate vicinity of the indent indicating that Ti2AlC is damage tolerant. The flexural strength and the fracture toughness were 275 MPa and 6.5 MPa (.) m(-1/2), respectively.