Preparation And Tribological Properties Of Ti(C,N) Base Self-lubricating Coatings

Friction and wear is one of the three major failure modes of components.It is estimated that the energy consumed in the friction process accounts for about 30%of the world's industrial energy consumption.At present,surface engineering technology is often used to coat the surface of components with a coating of anti-friction functional materials,in order to achieve the effect of anti-wear.Self-lubricating coating has been paid more and more attention by researchers for its excellent lubricating effect.In this paper,the self-lubricating coatings of C fiber,SiC whisker,flake graphite,TiC+TiB2 and metal Mo were prepared by plasma spraying,laser remelting and laser cladding respectively.The microstructure and phase of the coatings were characterized by SEM,XRD and EDS.Test the tribological performance of coating under room temperature and 200?and analyze the morphology after the friction and wear,the wear mechanism of the different lubricant conditions are obtained.1.Adding C fiber,SiC whisker and flake graphite to TiCN ceramic coating can improve the wear resistance and wear resistance of the coating.At room temperature,the best component TiCN+6%SiC whisker+5%flake graphite composite coating has the best wear resistance and wear resistance,and the friction coefficient is 0.32.Under the condition of200?composite coating have excellent tribological performance;Under lubricating oil lubrication condition,the bridged action of whiskers reduces the shedding caused by fatigue wear,so that the composite coating still has a low friction coefficient,which is about 0.1.2.After remelting,the coating becomes densier and has better tribological properties.After remelting of the optimal component coating,the friction coefficient remains basically unchanged,but the wear weight loss is 70%lower than that of the non-remelting coating.Before and after remelting,the forms of wear and failure are the coexistence of fatigue wear,adhesive wear and oxidation wear.The flake graphite film and the oxidation film generated in the friction and wear play a synergistic role in lubrication,so as to achieve the effect of anti-friction and wear.3.The optimal power of Ni60+Ti+B₄C+Mo coating prepared by laser cladding is 1600W,and the optimal powder ratio is Ni60+20%?Ti+B₄C?+5%Mo.Ti+B₄C powder generates TiC and TiB2 hard phases in situ in the cladding process,and Mo generates Mo2C hard phases in situ,which can significantly improve the friction reduction and wear resistance of the coating.The wear failure forms are abrasive wear,adhesive wear and oxidation wear.The friction reduction mechanism of TiC+TiB2+Mo coating is as follows:the hard phase uniformly distributed on the soft matrix plays a major role in the process of friction and wear,and the Mo added can play a role in friction reduction.