Dark, very hard, chemically resistant submetallic substances. The V-C system has two phases:
VC: Homogeneity region VC0.92-VC0.74; m.p. 2800°C. Crystal structure: B 1 (NaCl) type.
V2C: Homogeneity region VC0.4-VC0.5. Crystal structure: L 3 type
2V + C = V2C
The reactants, preferably in finely subdivided form, are intimately mixed and, if needed, also compressed into pellets. The reaction is then carried out in a high vacuum. At a temperature of 1300°C, approximately 24 hours, or at 2000 ℃ about 15 minutes, are required for homogenization of the product. The reaction is best carried out in a graphite crucible.
