High-performance PTFE composites from industrial scrap with enhanced strength and wear resistance.

Due to the high cost of raw materials, this work aims to utilize polytetrafluoroethylene (PTFE) scrap generated from industrial waste to produce composites possessing superior properties for potential use in various industrial applications. In this respect, PTFE-based composites reinforced with mono- and hybrid granite and boron carbide (BC) nanoparticles are produced using powder metallurgy (PM) technology. The sintered composites' physical, mechanical, tribological, and thermal properties and the phase composition and microstructure were investigated using X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) techniques, respectively. The results indicated that the phase composition of the prepared composites did not change. Adding granite and/or BC to the PTFE base increased the bulk density and the total porosity, while the relative density decreased. In addition, after adding 5 vol% granite/5 vol% BC (PTFE6 sample), there was a clear improvement in mechanical properties, including microhardness, ultimate, and Young's modulus, reaching 123.29%, 91.33%, and 74.17% compared with the unreinforced sample (PTFE0). Moreover, there was a noticeable improvement in the wear rate, fraction coefficient, and thermal expansion coefficient (CTE) value for the same sample, which decreased by approximately 37.17%, 36.50%, and 61.64%.