ИСТИНА

This study is focused on the difference in mechanical and tribological properties, and fracture of the coatings, which are designed using two different types of magnetron sputtering technology: high power impulse HiPIMS (pulsed) and direct current DC (non-pulsed). The work includes friction tests, calculation of internal stresses and microscopic study of the sample surfaces before and after friction, analysis of chemical composition of surface layers and wear particles, measuring of roughness before and after friction, indentation of initial and worn surfaces, and estimation of Young modulus of coatings before and after friction using analytical-numerical modeling. The difference in friction and wear mechanisms depending on the applied technique is analyzed. The results showed that friction coefficient against 100Cr6 balls and internal stresses are greater for DC coatings although, they have better resistance to brittle crack formation. Analysis of nano-roughness by AFM shows that worn tracks are very smooth even for initially rough surface. DC coatings have similar elastic properties before and after friction. HiPIMS coatings become more compliant after friction, probably due to formation of thin compliant film at the surface of the coatings.