Inorganic fullerene-like tungsten disulfide nanocoating for friction reduction of nickel–titanium alloys

Abstract

Aims: To fabricate a friction-reducing coating onto different nickel–titanium (NiTi) substrates using inorganic fullerene-like tungsten disulfide (IF-WS2) nanoparticles and to estimate in vitro friction reducing extent of the coating. Materials & methods: Different NiTi substrates were coated with cobalt and IF-WS2 nanoparticles film by the electrodeposition procedure. Coating composition analyses was made by scanning-electron microscopy, energy dispersive x-ray spectroscopy, x-ray powder diffractometry and x-ray photoelectron spectroscopy. Friction evaluation was carried out using standard tribological tests and an Instron® system. Results: Stable and well-adhered cobalt + IF-WS2 coating of the NiTi substrates was obtained. Friction tests presented up to 66% reduction of the friction coefficient. Conclusion: NiTi alloy is widely used for many medical appliances; hence, this unique friction-reducing coating could be implemented to provide better manipulation and lower piercing rates.