The paper presents results of investigations on the binderless nanostructured tungsten carbide (WC) cutting tools fabrication and performance. The scientific novelty includes the description of some regularities of the powder consolidation under electric current and the subsequent possibility to utilize them for practical use in the fabrication of cutting tools. The sintering process of WC nanopowder was performed with the electroconsolidation method, which is a modification of spark plasma sintering (SPS). Its advantages include low temperatures and short sintering time which allows retaining nanosize grains of ca. 70 nm, close to the original particle size of the starting powder. In respect to the application of the cutting tools, pure WC nanostructure resulted in a smaller cutting edge radius providing a higher quality of TiC/Fe machined surface. In the range of cutting speeds, vc = 15–40 m/min the durability of the inserts was 75% of that achieved by cubic boron nitride ones, and more than two times better than that of WC-Co cutting tools. In additional tests of machining 13CrMo4 material at an elevated cutting speed of vc = 100 m/min, binderless nWC inserts worked almost three times longer than WC-Co composites.

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The paper presents the results of investigations on the tribological properties of cutting tools after ion implantation. The research focused on the inserts made out of nitride ceramics IS9 (Si3N4 with additives) and combined ceramics IN22 (Al2O3 + TiCN) available on the market. The inserts rake surfaces were covered with yttrium and rhenium coatings by means of ion implantation with different dozes. Both unimplanted and coated surfaces underwent tribological tests of the block-on ring type. The experiments demonstrated that, in general, ion implantation with rhenium (Re+) and yttrium (Y+) provided a decrease in surface friction forces. In the case of IN22 ceramics, both rhenium and yttrium ions improved wear resistance of cutting inserts. On the other hand, Re+ implantation provided the best wear resistance of the IS9 ceramics.

In the paper, analysis of the curved profile measurement accuracy is described. Since there was no CAD model or other reference profile for the measured detail, the first step was to generate the reference contour of the cam using the technical drawing and tolerance requirements. The test campaign consisted of three experiments aimed at determining the effect of scanning velocity on the results of form deviation δ measurement, evaluation of deviation δ measurement uncertainty and the measurement repeatability. The scanning time was checked, too. The obtained results demonstrated feasibility of the chosen CMM and measurement strategy. It was found also that the measurement uncertainty did not depend on the scanning sampling step from 0.05 to 0.2 mm, and the true measurement time was for 30-40% longer than that expected from the nominal scanning velocity.

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