Mechanical and tribological properties of carbon fiber‐reinforced polyetheretherketone composite coatings by flame‐spraying method

Abstract The carbon fiber‐reinforced polyetheretherketone (CF/PEEK) composite coatings with two types of short CFs, that is, 300‐ and 600‐mesh, each in the contents of 10 and 30 wt% are deposited in comparison with the pure PEEK coatings by using a flame spraying method, respectively. The 300‐mesh CFs with intact morphology and the 600‐mesh CFs preserving fractured shape and higher graphitization degree are selected as the reinforced fillers in the CF/PEEK composite coatings. The flame‐sprayed CF/PEEK composite coatings show the increased porosity with the higher CF contents. The adding of CFs in the flame‐sprayed CF/PEEK composite coatings limits the thermal degradation of PEEK and restrains the PEEK crystallization showing low crystallinity degree and small crystallite size. The composite coatings in 10 wt% CF content exhibit the optimized nanoindentation behavior and tribological property. The 300‐mesh CFs with large length and intact morphology in flame‐sprayed CF/PEEK composite coatings lead to the increased surface hardness by 1.31 times over that of the pure PEEK coatings. The 600‐mesh CFs with higher graphitization degree contribute to better tribological property of flame‐sprayed CF/PEEK composite coatings with an order of magnitude lower specific wear rate.