Nano and Nanocomposite Superhard Coatings of Silicon Carbonitride and Titanium Diboride by Magnetron Sputtering

Superhard coatings (hardness >20 GPa) are being widely researched, driven by the need to use the components under different combinations of environments. Complex properties such as low friction and low wear, increased life time, and increased toughness are required in the same coating. Nanocomposite and nanocoatings are promising materials to achieve them. In the present communication, the author presents research findings on hard nanocomposite and nanocoatings of silicon carbonitride (SiCN) and titanium diborides by magnetron sputtering on Si and steel substrates. XPS, atomic force microscopy, and nanoindentation studies on both the films showed that they possessed high hardness, modulus, and significant elastic recoveries after unloading. These properties can be attributed to nanocrystalline dispersions of carbon nitride and silicon nitride phases in the amorphous SiCN matrix in nanocomposite SiCN thin films, whereas in the case of the TiB ₂ film, nanosize grains led to higher hardness.