The objective of the paper is to show that thin, hard coatings deposited on heavy-loaded machine components working in a non-conformal contact (e.g. gears) and lubricated with ecological oils, make it possible to increase the service-life of these components. The scuffing resistance was assessed by employing a high-resolution four-ball test method realized in a tester with continuously increasing load. Also another test method — FZG scuffing test — was realized using a back-to-back gear test rig. The test balls and gears were coated with thin, hard TiN and WC/C coatings deposited using arc-vacuum and reactive sputtering techniques respectively. The performed tests indicate that the presence of thin coatings on machine components gives a possibility of eliminating or reducing the content of toxic AW/EP additives in lubricating oils, as well as using ecological oils made of renewable resources, without any risk of a scuffing failure.

This content is only available via PDF.
You do not currently have access to this content.