Increasing the Wear Resistance of High-alloy Tool Steels for Cold Work with Multilayer Coatings TiN/TiCN and TiN/Ti-B-N Applied by the PACVD Process

The contribution compares the abrasion and erosion resistance of two high-alloy tool steels, X153CrMoV12‑1 and Böhler K390 Micro Clean, coated with multilayer coatings TiN/TiCN and TiN/Ti-B‑N. Multilayer coatings were applied to hardened and tempered samples by pulsed direct current (DC) plasma-assisted chemical-vapour deposition (PACVD) process in the Rübig PC 70/90 industrial vacuum furnace. The mechanical properties of the coating were tested by calottest, Rockwell‑C indentation and the micro hardness tests. Abrasion resistance was tested by the “Dry sand/Rubber wheel” and micro abrasion method. Erosion resistance was tested by exposing the surface of the samples to a jet of fine sand particles at an angle of incidence of 90 degrees for 60 min. Worn surfaces were analysed with a light and scanning electron microscope. It was found that increased resistance to abrasion and erosion wear is achieved on samples with higher substrate hardness and higher coating hardness, and better adhesion of the coating.