Various hard coatings have been widely used to improve the performance of tools and to extend tool life. Superlattices have very interesting properties, which are unattainable in bulk materials. The primary interest is in the mechanical properties with the secondary goal of improving the tribological properties of the surface. Among the different methods, the magnetron sputtering was found to be a good method to deposit high-quality superlattice coatings on tool materials because of easy control of composition modulation wavelength, crystal structure and stoichiometry of each layer.
In this work magnetron sputtering method is presented. By this method we have obtained Ti/N and TiN/NbN superlattices. We used as the substrate Si (100) wafers. Additionally 300 nm TiN and 300 nm NbN thin films evaporated onto Si wafers were used for comparing with our superlattices. X- ray diffraction method was used for the structural investigations ( both substrate and deposit) and evidence of layered (or not) deposit structure. The hardness of composite
( Si + multilayer) was measured using the Vickers intender with 5g load.
The production of a well defined multilayered structure was confirmed
( by XRD) for TiN/NbN superlattice grown onto Si substrate. This superlattice exhibited pure cubic structure with main visible (111) and (200) peaks. The hardness of the composite (substrate + deposit) had the highest value of 45 GPa.
Value of hardness of Ti/Nb superlattice is lower- 30 GPa. The hardness of the TiN/NbN superlattices deposited onto Si substrate had higher values than hardness of Si.
In this work the possibility of depositon of the superlattices onto Si wafers has been checked. The hardness results, especially for TiN/NbN superlattice, are very promising for improving of the wear resistance. The coatings demonstrates application prospects in the cutting tool industry.