Wear Rate of PcBN Cutting Tools Equipped with Nanolayered Protective Coatings

We consider the effect of protective PVD coatings of various chemical compositions on the wear rate of cutting tools equipped with polycrystalline superhard materials (PSHM) based on cubic boron nitride (PcBN). A coating of the nanolayered structure was applied to cutting inserts made of superhard composites of the BH group by a vacuum-arc method using a Bulat-6 setup. Previous tests, carried out under conditions typical for finishing hardened steel, demonstrated high efficiency of coatings containing Ti, Zr, and Cr nitrides. The (TiAlSiY)N/CrN coating is the most effective. The study of the kinetics of tool wear shows that under test conditions, the wear rate of tools along the flank surface of the wear chamfer h z of tools equipped with modified cutting inserts is significantly reduced by an average of 2.3 times. At the same time, no significant differences in the roughness of surfaces processed by tools with uncoated and coated composites were found under test conditions. The results also indicate that the coating does not decrease the wear rate of the tool equipped with PSHM of group BN when processing materials containing a significant amount of the carbide phase in their structure.