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In this work, combined gradient ZrC/Ni-nanodiamond ultradispersed diamonds (UDD) coatings were synthesized on the surface of knife blades made of hard alloy WC-2 wt.% Co by electroplating and cathode arc evaporation PVD techniques to increase the durability period of a wood-cutting milling tool. The microstructure, phase and elemental composition, microhardness, and adhesion strength of the coatings were investigated. Ni-UDD layer is not mixed with the ZrC coating and hard alloy substrate. Cobalt is present in Ni-UDD layer after deposition of ZrC. The ZrC/Ni-nanodiamond coating consists of separate phases of zirconium carbide (ZrC), a-Ni, and Ni-UDD. The maximum value of microhardness of the Ninanodiamond coating is 5.9 GPa. The microhardness value of the ZrC/Ni-nanodiamond coatings is 25 ± 6 GPa, which corresponds to the microhardness of the hard alloy substrate and ZrC coating. The obtained high values of the critical loads on the scratch track of the ZrC/Ni-nanodiamond coating in 24 N prove a sufficiently high value of the adhesion strength of the bottom Ni-UDD layer with WC-Co substrate. Pilot testing of ZrC/Ni-nanodiamond-coated cutting tools proved their increasing durability period to be 1.5-1.6 times higher than that of bare tools, when milling laminated chipboard.

The effect of sulfacyanization of ZrN and Mo+Mo 2 N coatings on the volume wear of hard alloy blade cutting knives when milling chipboard laminated wood was investigated. It is revealed that this treat ment reduces the volume wear of knife blades two times. Nitride coatings promote the hardness and defor mation resistance of blades. Sulfacyanization forms surface film containing C, S, and N. This film is deeply deformed through the edges and pores of carbide grains reducing friction and oxidation of blades in cutting.

The presented article focuses on measurements of extremely small dimensions in nanometrology using tactile probes. It addresses a newly developed method of precise measurements in nanometrology by touch probes, where the measurements are carried out on the machine SIOS NMM-1. The aim of this work is to determine accuracy of measurements on this machine. The main contribution of this work is a creation of a methodology for the measurement of precision parts and determination of accuracy of measurement when using this device in nanometrology. The work also includes methodology for the calculation of measurement uncertainty, a keystone in determining the accuracy of measurement in nanometrology. The article provides results of representative sets of measurements of ruby ball diameters, including the evaluation of statistical parameters and determination of the combined measurement uncertainty.

This paper presents the results of a study on the preparation and characterization of a Cr-DND/MoN detonation chromium-nanodiamond coating deposited on cemented tungsten carbide (WC–3 wt.% Co) mill blades using Arc-PVD and electrodeposition methods. The physical and mechanical characteristics of the coatings were investigated by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), XRD analysis, Raman spectroscopy, micro-identification, and scratch test (evaluation of the coating adhesion). It was shown that the Cr-DND/MoN coating consists of successive layers of Cr-DND (top), Cu (middle) and MoN (bottom) with separate phases of γ-Mo2N, α-Mo, α-Cu, Cr-DND and nanodiamonds. The Cr-DND composite electrochemical coating (CEC) was deposited from the conventional chromium plating electrolyte with the addition of nanodiamonds. The copper interlayer was deposited by the Arc-PVD method on the surface of the MoN coating to improve the adhesion strength of the Cr-DND CEC. The coating showed an optimum microhardness of about 14 ± 1 GPa and good adhesion with a critical load Lc of about 93 N. In addition to the expected experimental results, the coating has high wear resistance, confirmed by scratch tests.