Optimization of the deposition parameters of DLC coatings with the MCVA method

Purpose: The purpose of the present study was to determine the optimal values of selected deposition parameters of diamond-like-carbon coatings (DLC) with the modified cathodic vacuum arc (MCVA) method which ensure obtaining of their most advantageous properties from the perspective of their application for the coating on high-speed steel tool substrates for woodworking.Design/methodology/approach: An analysis was conducted of the investigations into the influence of the selected deposition parameters of DLC coatings on the accepted optimization criteria with the use of the Taguchi module. Adhesion, hardness and friction wear resistance were accepted as the optimization criteria of DLC coatings for high-speed steel substrates.Findings: It was established on the basis of the statistical analysis of the research results that in order to ensure a high adhesion of DLC coatings to high-speed steel substrates, a thick Cr sublayer (0.3 μm) and a DLC coating (1.8 μm) is to be used, which is deposited at a high argon pressure (0.25 Pa); no substrate bias (the floating potential) is to be used. In order to obtain high hardness and friction wear resistance, higher values of substrate bias voltages (-80 V) and a low pressure of argon (0.01 Pa) are to be used.Research limitations/implications: To evaluate with more detail the possibility of applying these coatings on tools. I will be kept industrial tests of wearing out tools covered with these DLC coatings.Practical implications: The properties of DLC coatings that are deposited with optimized parameters may indicate the possibility of their application for woodworking or tools for wood-like materials in order to increase their durability.Originality/value: From results of the optimization of selected deposition parameters of DLC on the Taguchi method is possible to appoint coating properties. Depending of the deposition parameters applied, it is possible to obtain DLC coatings in a wide range of hardness (20-60 GPa). The DLC coatings might be apply on high-speed steel knives for woodworking industry.