Preparation And Tribocorrosion Performance Of CrCn,TiSiN-Ag And Cr/CrN Coatings In Seawater

In recent years,the strategic positioning of China's marine economic development has been increasing,which has become one of the engines of economic development.The development of the marine economy is inseparable from the support of marine engineering equipment.However,due to the strong corrosiveness,low viscosity,high pressure and the existence of various forms of friction and wear during the operation of mechanical systems,key friction pair components in marine engineering equipment are facing more severe service conditions than those on land.It restricts the service performance of the marine engineering equipment.At present,the solution to this problem is coated on the substrate.The commonly used processes include multi-arc ion plating,spraying and so on.Therefore,three typical nitride coatings for seawater of CrCN,TiSiN-Ag and Cr/CrN were prepared on 316L,TC4 and Cu substrates by multi-arc ion plating technology.The microstructure of the coatings material was characterized and its mechanical properties,electrochemical properties and tribological properties were analyzed.The effects of different deposition bias voltages,Si-doping contents and substrate materials on the tribocorrosion behavior of the three coatings in seawater were studied.It will provide the abrasion mechanism of coatings on different substrates in seawater and references for the selection and preparation of anti-tribocorrosion coatings in seawater.The main research contents of this paper are following:1.The CrCN coatings on 316L,TC4 and Cu substrates under different bias voltages?-30V/-50V?have been prepared.The anti-tribocorrosion performances in simulated seawater were studied.It can be concluded that the coatings with bias voltage of-50V exhibit the better comprehensive mechanical properties and anti-tribocorrosion performances.It is mainly caused by more Cr₂N phase and nanocrystalline/amorphous mixed structure in these coatings.Meanwhile,the coatings on TC4 substrate have relatively good anti-tribocorrosion performances and the coatings on Cu substrate have relatively poor performances.2.The TiSiN-Ag composite coatings on 316L,TC4 and Cu substates were obtained.The anti-tribocorrosion performances in simulated seawater were studied.It can be concluded that 8wt.%Si-doped coatings exhibit the better comprehensive mechanical properties and anti-tribocorrosion performances.It is mainly caused by more nanocrystalline composite structures in these coatings.Meanwhile,the coatings on TC4substrate have relatively good anti-tribocorrosion performances and the coatings on Cu substrate were worn through.3.The periodic Cr/CrN multilayer coatings on 316L and TC4 substrates were obtained.The anti-tribocorrosion performances in simulated seawater were studied.It can be concluded that the coatings on TC4 substrate show the better comprehensive mechanical properties and anti-tribocorrosion performances.The main reason is that these coatings have less tensile stress in the deposition process and the crystal density of TC4substrate is large,the specific strength is high and the corrosion resistance is better.