Role of WS2, WS2+CrC and bonded coatings on damage and friction of Inconel 718 flat rough surfaces at high temperature

Inconel 718 flat rough surfaces were tested under fretting conditions at room and high temperature (600 °C). Analysis were focused on friction coefficient, damage and fretting regime. Several coatings were tested, and showed significant differences depending on the test temperature. The bonded coating offers good protection against fretting wear at ambient temperature but loses its properties at 600 °C where the CrC shows excellent durability and lower friction thanks to the formation of a few micrometers thin glaze layer. WS2 solid lubricant layers also show a similar protective behaviour at high temperature but under lighter normal loads and for a lower lifespan.