Abstract: In this paper， an aluminum phosphate binder was prepared by chemical synthesis. And aluminum phosphate composite coatings prepared by using binder， aluminum powder and different concentration of silica sol were fabricated on Q235 steel to form the films. The structure and morphology of the films were characterized by X-ray diffraction （XRD） and scanning electron microscopy （SEM）， and the corrosion behavior was studied through electrochemical and soaking tests. The results indicated that the addition of silica sol improved the film quality and corrosion resistance， meanwhile， increased the corrosion potential and impedance magnitude and decreased the corrosion current. In particular， the coating comprising 10％ silica sol exhibited the optimal film quality and corrosion resistance.
LUO Q， WU Z， QIN Z B， et al. Surface modification of nickel-aluminum bronze alloy with gradient Ni-Cu solid solution coating via thermal diffusion[J]. Surface and Coatings Technology，.[J].，309：, 2017, :106-113.-
ZHANG D W， QIAN H C， WANG L T， et al. Comparison of barrier properties for a superhydrophobic epoxy coating under different simulated corrosion environments[J]. Corrosion Science，.[J].，103：, 2016, :230-241.-
KARTSONAKIS I A， BALASKAS A C， KOUMOULOS E P， et al. Incorporation of ceramic nanocontainers into epoxy coatings for the corrosion protection of hot dip galvanized steel[J]. Corrosion Science，.[J].，57：, 2012, :30-41.-
HEYDARPOUR M R， ZARRABI A， ATTAR M M， et al.Studying the corrosion protection properties of an epoxy coating containing different mixtures of strontium aluminum polyphosphate (SAPP) and zinc aluminum phosphate (ZPA) pigments[J].Progress in Organic Coatings, 2014, 77(1):160-167