Reaction Synthesis and Pressureless Sintering of Cr2AlC Powder

This work was aimed to produce Cr2AlC powder through two-step reactions and to sinter it under a pressureless condition, and the related synthesis and sintering mechanisms were evaluated. Cr2AlC powder of ∼9 μm in size was produced using CrCx and Al powders and sintered to a relative density of ∼95.5%. The sintering was characterized by an activation energy of 267±23 kJ/mol and the mixed mode of sintering comprised of the surface diffusion mechanism and the transient liquid-phase sintering caused by melting of Al–Cr intermetallic impurities. The sintered sample exhibited Vickers hardness of 3.4 GPa.