The effect of lamellar zinc powder replacing a small amount of spherical zinc powder in alcohol-soluble inorganic zinc-rich coating on coating properties was studied by salt spray test, measurements of polarization curve and open circuit potential (OCP)-time curve, and electrochemical impedance spectroscopy (EIS) at a constant total oil adsorption of pigment and the ratio of pigment volume concentration (PVC) to critical pigment volume concentration (CPVC) being 0.77. It was found that when the mass fraction of lamellar zinc powder is in range of 5% to 30%, both saline and salt spray resistance of the coating is increased initially and then decreased with increasing dosage of lamellar zinc powder and reach their maxima at a replacement ratio of 20%. The coating prepared with 20% lamellar zinc powder has longer protection period as a sacrificial anode, better anodic dissolubility, and lower impedance at low frequency (0.2 Hz) as compared with the coating without partial replacement of spherical zinc powder with lamellar one.%在颜料总吸油量一定、各配方中颜料体积浓度(PVC)与临界颜料体积浓度(CPVC)之比为0.77的条件下,通过盐雾试验、极化曲线、开路电位(OCP)-时间曲线和电化学阻抗谱(EIS)研究了片状锌粉取代醇溶性无机富锌涂料中少量球状锌粉对涂层性能的影响.研究结果表明,在片状锌粉取代比为5％ ～ 30％范围内,涂层的耐盐水和耐盐雾腐蚀时间随片状锌粉取代比的增加而先增加后减少,在取代比为20％时达到最大值.与未取代涂层相比,取代比为20％的涂层其牺牲阳极保护时间更长,阳极溶解性能更好,低频(0.2 Hz)阻抗更小.
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