Owing to their attractive properties, diamond-like carbon (DLC) coatings are becoming more and more important in the field of machine components. Under dry sliding conditions, many types of thin DLC coatings show excellent wear protection and low friction, typically in the range of 0.1–0.01. The low friction nature, excellent wear and corrosion resistance, high hardness, high elastic modulus and high thermal and chemical stability of these coatings make them good candidates for a wide range of tribological applications. However, successful application of coatings in machine component applications require adequate performance not only in dry but also under oil-lubricated conditions. This has many reasons. Firstly, the tribological properties of unlubricated DLC coatings are sensitive to the ambient atmosphere, especially the relative humidity. Further, the lubricant also serves other functions in the mechanical system, such as cooling and wear particles removal. Therefore, despite the low-friction nature of DLC coatings, a majority of coated machine components will continue to be operated under lubricated conditions, and will initially use the same oils as originally developed for metallic surfaces. The aim of the present investigation was to obtain some further understanding of the mechanism responsible for low-friction behaviour of W-containing DLC coatings (W-DLC) when lubricated with EP additivated oil. Boundary lubricated wear and friction tests were performed under reciprocating sliding motion using a high frequency test rig and a contact pressure of 1.5 GPa. Additionally, some of the tests were performed in a load-scanning reciprocating test rig, with the contact pressure being in the range from 2.4 to 5.6 GPa. The influence of concentration of a sulphur-based EP additive on the friction behaviour was investigated.
本文由桑尧热喷涂网收集整理。本站文章未经允许不得转载；如欲转载请注明出处，北京桑尧科技开发有限公司网址：http://www.sunspraying.com/
|
