Tribological CCF-PEEK transfer film growth on cutting tool coating

To show transfer film growth of continuous carbon fibre reinforced thermoplastic poly-ether-ether-ketone (CCF-PEEK) on cutting tool coating, dry-sliding tribological behaviours of single-layer diamond-like carbon (DLC), titanium nitride (TiN), titanium aluminium nitride (TiAlN) and diamond deposited on cobalt-based cemented carbide (WC-Co) against CCF-PEEK were studied at atmospheric room temperature, respectively. CCF-PEEK showed little affinity to DLC, but continuous CCF-PEEK transfer films with micron-level thickness grew on TiN, TiAlN and diamond, and raising load facilitated the growth. Deposition of DLC significantly lowered the friction of WC-Co whereas TiN, TiAlN and diamond exhibited higher friction than WC-Co. Much larger amounts of CCF-PEEK wear debris were produced on diamond than on TiAlN, TiN and DLC. Formation mechanisms of CCF-PEEK transfer films and the effect on friction are discussed. This study suggests that DLC can be used as countermate surfaces of CCF-PEEK composite with low friction and little CCF-PEEK wear debris.