Orenburg State University, Orenburg, Russia

E. S. Kozik, Associate Professor at the Department of Descriptive Geometry, Engineering and Computer Graphics, Candidate of Technical Sciences, e-mail: ele57670823@yandex.ru
E. V. Svidenko, Associate Professor at the Department of Materials Science and Materials Engineering, Candidate of Technical Sciences, e-mail: tzvetkova.katia2016@yandex.ru

A modern approach to enhancing the performance of cutting tools involves the use of various techniques for applying wear-resistant coatings to the tool surface. Such choice comes down to the fact that this layer ensures high wear resistance of the item whereas the host material acts as a carrier. The authors of this paper applied a wear-resistant nACo coating to hard alloy of 6WH10F grade. Pillar-shaped specimens of 6WH10F hard alloy with the diameter of 10 mm and the height of 10 mm were used for the study. A nACo(Ti, Al)N coating was applied to them in a PLATIT unit at 550 ^oC. The Physical Vapour Deposition (PVD) technique was applied with plasma generation, while also using the conventional ARC cathode technique (PL 70, PL1001, PL 2001). Coatings with pre-defined thicknesses of 2 to 3 μm were applied to all items. This allowed to obtain a batch of items with homogenous coatings and ensure a high reproducibility of the coating quality. The layers were applied evenly, the absence of shells or cracks being an indicator of good adhesion. The authors determined the boundary between the coa ting applied and the substrate, as well as the coating thickness. With the help of a JEOL electron microscope operated in automatic mode, the concentration of chemical elements was analyzed in the deposited layer — i. e. in the outer and intermediate layer (an intermediate layer between the coating and the hard alloy). Due to this, the presence of the following elements was identified based on pre-defined identifications: N, C, B, O, Al, Si, P, S, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Nb, Mo, Ag, W, Au. To determine the performance of specimens with coatings and without them, they were tested for diamond-abrasive wear in a special unit, with the test durations of 3, 6 and 9 minutes. The technique implies rubbing specimens against a diamond cup (‘АСЧ 100×90 С22 4 82-01’) per GOST 17367–71, with the load of 1 N applied to 1 mm² of the specimen area. The mass wear, wear intensity and rate, as well as wear resistance were also calculated. The authors would like to thank A.A. Stepanov for preparation of and deposition of coatings to specimens.

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