COMPARATIVE STUDY OF MECHANICAL AND CORROSION PROPERTIES OF COATING ON THE BASIS OF ZrN AND TiN SOLID SOLUTIONS

ZrN, (Zr,Ti)N, (Zr,Hf)N, (Zr,Nb)N, (Ti,Zr,Hf)N, and (Ti,Zr,Nb)N coatings mechanical and corrosion properties were investigated in this work. Coatings were deposited by vacuum arc deposition technique on Ti-6Al-4V titanium alloy. Microhardness measurements, tribological and scratch tests, profilometry, electrochemical corrosion tests, and scanning electron microscopy were used as investigation techniques. The highest microhardness value (36.2 GPa) was observed for the (Zr,Hf,Ti)N coating, and the lowest value (12 GPa) for the (Zr,Nb)N coating. The highest critical forces Lc3 during scratch tests were found for coatings containing hafnium. It was revealed that the shape of anodic potential dependence on time during electrochemical corrosion tests in galvanostatic mode (3% NaCl environment) was strongly dependent on coating type. The time necessary to reach the maximum stable value of anodic potential can be an indirect parameter of corrosion resistance. (Zr,Nb,Ti)N coating demonstrated the best corrosion resistance in used test regimes.