LAUSR

Abstract Despite interest, no one to the best of our knowledge has compared the physical, mechanical, and tribological properties of nitride-based TiAlN and CrAlSiN coatings, nor diamond-like ion-plasma coatings (DLC). In order to identify the physical and mechanical properties, including the elastic modulus E and hardness H , we used nanoindentation methods, while experimental tribological testing of coatings was carried out on a TRB tribometer (Anton Paar TriTec SA). These tests revealed that during operation in the contact area of splined joints, a multilayer coating has better mechanical properties than a monolayer one under the testing conditions at specific loads comparable to operating loads. At the same time, a DLC coating features a much lower friction coefficient than do nitride systems. In addition, the paper presents the results of keeping friction units under observation by the acoustic emission (AE) method, which makes it possible to determine the running-in time for both coated and uncoated friction units.