Effect of reinforcement on wear debris of carbon nanofiber/high density polyethylene composites: Morphological study and quantitative analysis

Polymeric nanocomposites are promising tribological materials. However, the wear debris generated on the sliding surface of composite materials is highly affected by the nanofillers used (types, surfaces, etc.). In this study, based on the high density polyethylene (HDPE) composites with various carbon nanofibers (CNFs) prepared, the effects of CNF concentration and surface modification on morphology and size distribution of wear debris were examined. The individual wear particle morphology was observed with a scanning electron microscope (SEM). The particle size distributions of the wear debris were statistically analyzed based on the optical microscope imaging for all the debris collected after 24 h of wear testing. In addition, the influence of various CNFs (untreated and organosilane treated) on debris components was analyzed by both differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA) measurements. The results revealed that there were less mechanical damage and a lower proportion of large particles in the wear debris for the nanocomposites with heavily organosilane coated CNFs.