DLC Films in Mechanical and Manufacturing Industry

In this chapter, diamond-like carbon (DLC) films for the manufacturing industry are discussed. Section 2 is dedicated to the production of a-C:H coatings by PACVD technology and the difficulty of the control of the plasma when it is generated by biasing the parts to be coated. This section also describes how process parameters can be interconnected and how they can influence the coating properties. Section 3 is related to some functional characterisations of DLC-coated parts that allow checking of the coatings properties and quality. The combination of coatings allows improving the performances of DLC. This can be achieved in vacuum equipment that can do both PVD and PACVD processes. It is particularly interesting to combine a hard chromium nitride layer deposited by reactive magnetron sputtering and a DLC top layer. This process can be used to increase the scratch resistance of DLC. Some tribology characterisations are also discussed in Section 4. These tests are very important for the optimisation of a DLC coating as they can, in some case, simulate the real working conditions.