The effect of heat treatment on the mechanical, tribological and load-carrying properties of PACVD-coated tool steel

The investigation included TiCN-coated P/M high-speed steel, with 12 different combinations of the vacuum heat treatment, the deep-cryogenic treatment and plasma nitriding, which were investigated as a way of simultaneously improving the mechanical, tribological and load-carrying properties of tool steel. The results show that for the most demanding forming operations the substrate toughness is far more important than the hardness, especially at elevated temperatures, with just a vacuum-heat-treated steel substrate giving the best support for the top coating.