Influence of the base pressure in deposition of a‐SiCx interlayers for adhesion of Diamond‐Like Carbon on metallic alloy

Diamond‐like carbon (DLC) is an amorphous material widely used in industrial applications due to its chemical, mechanical, and tribological properties and, also, for decorative purposes. However, its low adhesion to ferrous alloys reduces its effectiveness in certain applications, necessitating the use of adhesion interlayers to reduce stresses at the interfaces and enhance the density of strong bonds. In this context, the factors that promote good adhesion in this system and specify the parameters must be understood in detail. Thus, the present study aims to assess the influence of the base pressure on the deposition of an amorphous silicon carbide adhesion interlayer between DLC coating and a ferrous alloy substrate. Microstructural, physicochemical, morphological, and mechanotribological analyses were conducted to understand the adhesion behavior in terms of structural and chemical aspects. In addition to the influence of the interlayer thickness, the elemental Si/C ratios and the relative oxygen content have an impact on the maximum load supported by the coatings, as well as the different delamination mechanisms generated in adhesion tests.