Effect of the nonstoichiometry of tantalum carbide TaCy on the particle size of nanopowders prepared by milling

The effect of the nonstoichiometry of tantalum carbide TaCy on the size of particles in nanocrystalline powders prepared by milling has been investigated experimentally for the first time. It has been shown that the effect of the nonstoichiometry on the milling manifests itself in the concentration dependences of the parameters of the crystal structure, energy of interatomic bonds, and elastic properties of the milled nonstoichiometric compound. The experimental data on milling of the tantalum carbide TaCy (0.81 ≤ y ≤ 0.96) have been compared with the theoretical dependences of the particle size D of nanopowders on the milling time t and the composition y of the nonstoichiometric cubic carbides TaCy. It has been established that, under otherwise equal conditions, the milling for 15 h makes it possible to obtain carbide powders with an average particle size of ∼20 nm and a specific surface area of 25 m2 g−1.