Novel thermodynamically stable and oxidation resistant superhard coating materials

摘要: Abstract A theoretical concept for the design of novel, nanocrystalline and thermodynamically stable materials with hardness ≥50 GPa (about 5000 kg mm−2), elastic modulus ≥500 a high stability against oxidation in air up to 800°C is described together its experimental verification on several systems nc-MexN/a-Si3N4 (Me  Ti, W, V). The based avoiding formation multiplication dislocations phase, blocking crack propagation 0.3–0.5 nm thin amorphous tissue. principles such thermodynamic criteria segregation nc- a-phases, which necessary preparation materials, are discussed. Several micron thick films have been prepared by plasma CVD at rate 0.6–1 s−1 from corresponding metal halides, hydrogen, nitrogen silane deposition temperatures ≤550°C. low content chlorine ≤0.3 at.% assures their corrosion air. Upon microindentation load ≥100 mN show remarkably recovery about 80%. Unlike diamond, c-BN, C3N4 these relatively easy prepare.