Recent progress in the superhard nanocrystalline composites: towards their industrialization and understanding of the origin of the superhardness

摘要

Recent progress is presented regarding the development of plasma induced CVD technique for coatings of non-planar and thick tools and of the understanding or the origin of the high thermal stability of the nanocrystalline TiN/amorphousSi{sub}3N{sub}4 superhard coatings up to 1100℃. A chlorine free, combined plasma CVD and PVD technique was developed for the deposition of superhard nc-TiN/c-BN nanocomposites. These coatings are compatible with the majority of engineering materials,such as ferrous and aluminum alloys and others. Their hardness reaches 70 GPa and elastic modulus E/(l-ν{sup}2)≈585 GPa. An industrial production reactor was built which enables one to deposit such coatings on cutting tools.