Extreme environment tribological study of advanced bearing polymers for space applications

• Published in: Tribology international 2021-01, Vol.153, p.106634, Article 106634
• Main Authors: Bashandeh, Kian, Tsigkis, Vasilis, Lan, Pixiang, Polycarpou, Andreas A.
• Format: Article
• Language: English
• Subjects: Bearing materials; Coatings; Coefficient of friction; Contact pressure; Cryogenic; Disks; Elevated temperature; Extreme environments; Fluoropolymers; Lubricants; Lubricating properties; Polymers; Self lubrication; Space; Space applications; Transfer layer; Tribology
• ISSN: 0301-679X; 1879-2464
• DOI: 10.1016/j.triboint.2020.106634

Polymers with self-lubricating properties have been employed in various applications as bearing components and tribological surfaces, particularly where the use of liquid lubricant is infeasible, such as space-related applications. This study reports on tribological solutions for extreme temperature ranging from −196 to 300 °C, which simulates extreme operating conditions that bearing materials in space will encounter. Tribological performance of three polymeric-based coatings, namely ATSP-, PEEK-, and Fluoropolymer-based coatings was evaluated. Inspired by the benefit of transfer layer, we deposited the coatings on both pins and disks to simulate polymer sliding on pre-deposited “transfer layer.” The ATSP-based coatings showed excellent tribological performance with low coefficient of friction and unmeasurable wear within a wide temperature range and constant contact pressure of 1 MPa. •ATSP coating showed unmeasurable zero wear from −196 to 300 °C at pressure of 1 MPa.•PEEK coating showed comparable COF and wear with ATSP but did not survive at 300 °C.•Fluoropolymer coating showed high COF at 25 °C and to a lower extent at 150 °C.•Proton radiation was ineffective in tribological performance of ATSP coating.