Mechanical properties of composite ceramic coatings plasma-sprayed on magnesium alloy

Aiming at the reality of aluminium piston surface easy scratches,in this paper the composite ceramic coating was deposited on XGFH-3 aluminium substrate by plasma spraying with composite ceramic powder prepared by mechanical ball milling and PVA granulating technology.The bond strength between the coating and substrate,the coating microhardness and the wear resistance for coating and substrate were measured by using oxygen to feed powder without transition layer.The results showed that the maximum bond strength,19.07MPa,for the coating sprayed with powder milled for 16h were reached.The maximum microhardness of the coating,HV0.11105,was realized,which was 16 times harder than the substrate.The wear mass per unit area of the substrate was about 8.5 times larger than the coatings,of which the maximum,13.6 times,was realized.