Study On The Preparation Of Ceramic Coatings On Carbon Fiber Reinforced Composite Surface By Plasma Electrolytic Cathode

Carbon fiber reinforced composites is one of the most advanced composite materials,which has been widely used in various fields such as the field of aerospace.However,some drawbacks still remain as it has poor stability of oxidation resistance under high temperature.The plasma electrolytic cathode technology is a new technology of material surface processing,which can be used under normal temperature and pressure,with simple device,without regard to the appearance of the potential materials.This article uses the plasma electrolytic cathode technology to fabricate ZrO₂-Y₂O₃ composite ceramic coatings on the surface of carbon fiber-reinforced silicon carbide composites and carbon fiber-reinforced resin composites material.The process parameters and its effect on the preparation and properties of coatings were discussed.The process parameters includes deposition voltage,deposition time and particle concentration?SiO₂/SiC?.Static oxidation test was carried out on the samples of sediment and deposition mechanism of the coating was analyzed.Through the experiments and the analysis of the deposition coating by using SEM,EDS and XRD,this article mainly draw these conclusions:?1?ZrO₂-Y₂O₃ composite ceramic coating can be used on the surface of carbon fiber-reinforced silicon carbide composite and carbon fiber-reinforced resin composite material by using plasma electrolytic cathode.?2?When using carbon fiber reinforced silicon carbide composite to prepare the composite ceramic coating with SiO₂ contained,SiO₂ in the solution affects the performance of the coating because the deposition time and the morphology of the coating have been affected.A quite good combination of parameters is when the deposition voltage is 170V and the SiO₂ in the solution reaches lg/L.?3?When using carbon fiber reinforced silicon carbide composite to prepare the composite ceramic coating with SiC contained,the amount of SiC in the solution as well as the voltage have different influences on the coating.A quite good combination of parameters is when the deposition voltage is 170V and the SiC in the solution reaches 5g/L.?4?When using carbon fiber reinforced resin composite to prepare the composite ceramic coating with SiO₂ contained,SiO₂ in the solution affects the performance of the coating because the deposition time and the morphology of the coating have been affected.A quite good combination of parameters is when the deposition voltage is 170V and the SiO₂ in the solution reaches 5?10g/L.?5?Under certain deposition voltage,cathode surface forms continuous covering.Increasing the voltage causes it to discharge and produces plasma.The whole process of plasma discharge causes a series of high-energy physical and chemical effects such as electrochemical and thermochemical effects,which makes ZrO₂-Y₂O₃ ceramic composite coating deposited on the surface of substrate.