Development of low friction wear-resistant coatings

Research has been performed to design a multifunctional coating combining TiN with MoSx resulting in a wear-resistant coating with a low coefficient of friction (COF). The coatings are deposited by a combined physical vapour deposition technique of E-gun evaporation and magnetron sputtering in a BAI640 equipment. Pin-on-disk (POD) measurements at approximately 50% RH against a corundum (Al2O3) ball show a significant decrease in COF compared with the results for a standard TiN coating. The incorporation of a soft phase in the TiN matrix did not lead to a decrease in hardness. The combination of a low COF and high hardness results in a decreased wear rate approximately 20 times lower in POD and 500 times lower in fretting compared to the standard TiN coating. The performance of the composite coating is tested in a drilling application and shows an increased lifetime.