SLPMC – NEW SELF LUBRICATING POLYMER MATRIX COMPOSITES FOR JOURNAL AND BALL BEARING APPLICATIONS IN SPACE

摘要

The paper is surveying the results of the ESA-projectrn“SLPMC” covering the development of a selflubricatingrnpolymer composite based on PTFE for use inrnbearings. The two targets of this project were torninvestigate lubrication mechanisms in PTFE-basedrncomposites under tribological conditions relevant tornspace applications (air, dry nitrogen, vacuum). Andrnsecondly, to develop a new composite to fulfil futurernneeds by space applications. Hence, in the frame of thisrnproject several new composites based on PTFE-matrixrnwith different kind of fillers were defined, manufacturedrnand tested on material level. From the most promisingrnvariants bushes for journal bearings and cages for ballrnbearings were machined. Ball bearing tests were done inrnhigh vacuum up to 10 million revolutions.rnThis paper summarises the main results from the projectrnon material level focusing on tribological results derivedrnby pin-on-disc tests. The influences of parameters likernload, speed, atmosphere and temperature are discussedrnand compared to other already known materials. Thernpaper also reports the findings from final ball bearingrnand plain bearing tests.