In this research, Cr-Al-Ti-N coatings on SKH 51 tool steel were prepared using a cathodic arc evaporation technique. The quaternary (CrxAl1−xTi0.15) N coating with the x value between 0.20 and 0.60 were studied in comparison to the TiAlN coating. The morphology of the surface coating was examined in cross-section using an optical microscope and field emission scanning electron microscope. Micro Vickers Hardness was used to measure the mechanical properties of the coating. Phase analysis was conducted using x-ray diffraction. The oxidation resistance of the coating was evaluated in ambient air at different temperatures up to 1100 °C. It was found the difference in chemical composition of the coating plays an important role on the quality of its microstructure, hardness, and oxidation resistance. The AlTiN coating showed a smooth surface and columnar structure, whereas micro-particles are observed on CrTiAlN-coated surfaces. The high Cr content in Cr-Al-Ti-N coatings indicates a high hardness value of 3284 HV and high oxidation resistance of up to 1000 °C.
Journal of the Australian Ceramic Society – Springer Journals
Published: Sep 1, 2021
Keywords: Oxidation resistance; CrAlTiN coating; Cathodic arc evaporation