Diamond deposition on steel substrates using intermediate layers

Diamond deposition on steel substrates is an interesting topic for tool production. Till now WC–Co hardmetal and ceramic tools have been coated with low-pressure diamond.One of the main problems of coating steel substrates is their reactivity with carbon. During diamond deposition the carbon diffuses into the substrate and its content can increase to several wt.% destroying the steel properties.In this study steel substrates were first coated with industrially available intermediate PVD-layers (CrN, TiAlN, TiCN, TiN, WC/C) and then diamond was deposited.Diamond nucleation and growth and additionally the influence of the intermediate layers on the carbon diffusion were studied. Metallographic studies showed if or if not the interlayer could protect the steel against the carbon attack.