The need to develop products with superior performance has led to the development of new materials and heat treatments. In the case of tools, well designed and controlled heat treatment is crucial to achieve appropriate combination of superior properties. In the huge number of heat treatment and surface engineering techniques, deep cryogenic treatment (DCT) shows very promising results. However, despite the potential and capability of DCT, these processes are still hardly known and implemented in practice. The main reason lies in the fact that the development of DCT has been mainly empiric, without a clear understanding of the scientific basics. Furthermore, for many years DCT had the reputation of being a quick fix for poor heat treatment practice. And although many different studies on DCT have been conducted, waste diversity of steel grades and heat treatment parameters were used and different testing methods applied, resulting in DCT effects being reported as highly positive, neutral and even negative. This makes comparison and true evaluation of DCT effectiveness practically impossible.
The aim of our research work was to systematically evaluate the effectiveness of DCT when it comes to tribological properties and wear resistance of tool steels, including influence of steel type, composition and hardening temperature. Since tools are subjected to different contact conditions and wear mechanisms, which require different tool steel grades, three representatives from each group (HSS, hot work tool steel and cold work tool steel) having different combination of alloying elements were selected and DCT treated in combination with quenching from high and low austenitizing temperature. Effect of DCT was evaluated in terms of abrasive and adhesive wear resistance under sliding, galling resistance in forming and impact wear resistance. Finally the results were correlated to changes in microstructure, hardness and toughness.