Tribological characterization of poly ether ether ketone peek filled with carbonaceous solid lubricants and synthetic diamond particles

Abstract

Polymers and composites are important tribo-materials for newlineengineering components like gears, bearing cages, artificial human joint newlinebearing surfaces, and bearings for space applications. Most listed applications newlinedo not need oil/grease for lubrication and work in dry sliding conditions, newlinedemanding self-lubricative nature. Polymeric bearings are generally used newlineunder low-pressure velocity conditions since they cannot sustain high newlinefrictional heat. Research efforts continuously focus on developing polymer newlinecomposites with a medium-pressure velocity limit capable of working under newlineharsher conditions, along with a low friction coefficient and wear. The thesis newlinefocuses on developing polymer composites based on PEEK (Poly ether ether newlineketone) as a matrix with various carbonaceous solid lubricants (carbon newlinenanotube, graphene, graphite) and ceramic particles of synthetic diamond. newlineThe filler particles of carbonaceous solid lubricants and synthetic diamond newlinewere incrementally incorporated into various concentrations through the newlinepowder mixing process, followed by the hot press sintering method. Their newlineproperties and performances were evaluated by chemical, mechanical, newlinethermal, and tribological characteristics. Various techniques such as FTIR newline(Fourier-transform infrared spectroscopy), SEM (Scanning electron newlinemicroscopy), XPS (X-ray photoelectron spectroscopy), Micro-Raman newlinespectroscopy, and 3D surface roughness were used for tribo surface analysis newlineto study the wear mechanisms and related self-lubricating phenomena. newlineThe first study focuses on the wear characteristics modification of a newlinehigh-function tribo PEEK composite fabricated through the spatial newlinedistribution of Bamboo Carbon NanoTube (B-CNT) with incrementally newlineblended networks of sub-micron high thermal conductivity synthetic diamond newlineparticles. With the addition of filler particles, the hardness of the composite newlinewas increased by 25%, and thermal stability improved by about 25 ºC due to newlinethe strengthening effect of diamond particles.