Journal of the American Ceramic Society, Vol.91, No.4, 1357-1360, 2008
New MAX-Phase compounds in the v-cr-al-c system
New layered compounds, (V0.5Cr0.5)(3)AlC2, (V0.5Cr0.5)(4)AlC3, and (V0.5Cr0.5)(5)Al2C3 were synthesized by reactive hot pressing V, Cr, Al, and graphite powders. The crystal structures of these new phases were determined using a combination of X-ray diffraction and scanning transmission electron microscopy. (V0.5Cr0.5)(3)AlC2 is isotypical to Ti3AlC2; while (V0.5Cr0.5)(4)AlC3 has the Ti4AlN3 or alpha-Ta4AlC3-type crystal structure. (V0.5Cr0.5)(5)Al2C3 is formed by periodically stacking of half-unit cells of (V0.5Cr0.5)(2)AlC and (V0.5Cr0.5)(3)AlC2.