Continuously Growing Ultrathick CrN Coating to Achieve High Load-Bearing Capacity and Good Tribological Property

Continuous growth of traditional monolayer CrN coatings up to 24 h is successfully achieved to fabricate ultrathickness of up. to 80 pm on the 316, stainless steel substrate using a multiarc ion plating technique.. The microstructures, mechanical properties, and tribological properties evolution with the CrN coating continuously growing was evaluated in. detail. The-transmission electron Microscopy observations and inverse Fourier-filtered images reveal a relaxation mechanism during the continuous growth of CrN coating, which can lead to a decrease in the residual stress when coating growth time exceeds 5 h. The scratch test and friction test results, both show that the load-bearing capacity of coating is significantly increased as CrN coatings growing thicker. During the scratch test, the ultrathick CrN coating of thickness 80.6 mu m is not failed wider the load of 180 N, and the dominant failure mechanism is the cohesive failure including wedge spallation and cracking. The dry-sliding friction test results show the mean coefficient of friction and the wear rate of ultrathick CrN are respectively decreased by 17.2 and 56.8% at most compared with the thin coating (thickness is 5.4 mu m). The,ultrahigh load-bearing capacity and, excellent tribological property are attributed to the relaxation mechanism and limited contact pressure as the coating grows continuously.