Diamond-like carbon coating in tribological applications

Abstract

This thesis is a literary study of diamond-like carbon coatings, their properties, deposition methods and performance in tribological applications. In applications the focus is on bearings and gears as they contribute to major part of wear and friction production in gearboxes. Gears and bearings suffer from surface failures which cause reliability issues. The DLC coatings are studied to improve resistance against wear, pitting and scuffing. Some coating suppliers are presented to give insight of the industrial coatings that are available.

The aim of thesis is to give basic understanding of DLC coatings. Some studies are presents as an example of DLC coatings which are used in laboratory tests to enhance properties of the components. The tribological performance of the DLC depends on multiple factors, for example, load, lubrication condition, coating type and counterface material. The DLC shows improved lifetime under certain parameters but more tests with specific conditions are needed because comprehensive conclusions cannot be made solely based on this thesis.