Investigations on Mechanical and Tribological Behavior of dcMS/HPPMS CrN and (Cr,Al)N Hard Coatings Using Nanoscratch Technique†

In this paper, interfacial adhesion strength and tribological behavior of systems, consisting of CrN and (Cr,Al)N coatings and AISI 420 steel substrate are investigated. The coatings are deposited using a hybrid technology consisting of direct current and high power pulse magnetron sputtering dcMS/HPPMS. Conventional Rockwell and scratch tests as well as nanoscratch analyses are performed. For the nanoscratch tests, a Berkovich and a conical indenters are used. Damage mechanisms are analyzed using Scanning Electron Microscopy (SEM) and explained by the plastic work from the nanoindentation tests. Investigations show a stronger interfacial adhesion strength and a higher abrasion resistance of the system AISI 420/(Cr,Al)N compared to the AISI 420/CrN.