Tribological behavior of polytetrafluoroethylene coatings based on LY12 substrates in the space environment

Abstract

The spacecraft space radiation environment was simulated by 60 Co source. The polytetrafluoroethylene (PTFE) coatings were fabricated on LY12 substrates. And the effect of gamma (γ) irradiation on the tribological behavior of PTFE coatings under vacuum conditions was investigated. Results indicate that the radiation dose has insignificant effect on the friction coefficient of PTFE coatings, and the wear of PTFE coatings reduces with the increase of gamma dose. As the gamma dose was 100 kGy, the friction coefficient of the PTFE coatings first increased with the increase of sliding velocity and then decreased, and the wear of the PTFE coatings decreased with the increase of sliding speed. As the gamma dose was 100 kGy, the friction coefficient of the PTFE coatings first decreased with the increase of load and then increased, and the wear rate of PTFE coatings increased with the increase of load. Scanning electron microscope was utilized.

Development and Verification Experiment of In-Situ Friction Experiment Device for Simulating UV Irradiation in Space

“…They specify that PTFE copolymer or other polymers are prone to degradation by a number of destructive factors in the space environment like mass losses and mechanical degradation of PTFE during vacuum UV). And in the last reference [ 24 ] the effect of gamma (γ) irradiation on the tribological behavior of PTFE coatings under vacuum conditions was also discussed. The PTFE was presented as a popular polymer solid lubricant and some characteristics of it, like resistance to the chemical attack in a wide variety of solvents and solutions, high melting point, low coefficient of friction, and biocompatibility.…”

Psychology-Based Research on Unsafe Behavior by Pedestrians When Crossing the Street

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