Abstract
An unbranched perfluoropolyether (PFPE) 815Z is the current ball bearing lubricant for space applications. Measurements of elastohydrodynamic lubrication (EHL) oil film thickness have been carried out to assess the lubricating performance of PFPE with average molecular weight of 9200 using an optical interferometric technique under mean Hertzian pressure 0.45 GPa. The film thickness of 815Z became less than predicted film thickness from Hamrock and Dowson formula for EHL central film thickness. There are two main explanations why PFPE is inferior to mineral oil in their ability to form EHL films, temporary viscosity loss and permanent viscosity loss. In order to elucidate the results, measurements of permanent viscosity loss under mean Hertzian pressure from 0.41 GPa to 2.67 GPa have been carried out using the thrust ball bearing. There results show that the degree of the permanent viscosity loss depends on Hertzian pressure, occurrence of permanent viscosity loss of 36 % with 2.67 GPa and 2 % with 0.41 GPa.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
