New Solid Solution MAX Phases: (Ti-0.5, V-0.5)(3)AlC2, (Nb-0.5, V0.5)(2)AlC, (Nb-0.5, V-0.5)(4)AlC3 and (Nb-0.8, Zr-0.2)(2)AlC

We synthesized the following previously unreported aluminum-containing solid solution M(n+1)AX(n) phases: (Ti-0.5, V-0.5)(3)AlC2, (Nb-0.5, V-0.5)(2)AlC, (Nb-0.5, V-0.5)(4)AlC3 and (Nb-0.8, Zr-0.2)(2)AlC. Rietveld analysis of powder X-ray diffraction patterns was used to calculate the lattice parameters and phase fractions. Heating Ti, V, Al and C elemental powders-in the molar ratio of 1.5: 1.5: 1.3: 2-to 1, 450 degrees C for 2 h in flowing argon, resulted in a predominantly phase pure sample of (Ti-0.5, V-0.5)(3)AlC2. The other compositions were not as phase pure and further work on optimizing the processing parameters needs to be carried out if phase purity is desired.