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本文利用电化学测试方法,开展了水泥砂浆模拟孔隙液中球墨铸铁表面钝化膜成膜过程的测试研究,分析了球墨铸铁电极的腐蚀电位和电化学阻抗谱及电荷转移电阻随模拟孔隙液碱度的变化规律,获得了球墨铸铁表面钝化膜成膜条件和成膜时间,结果表明:水泥砂浆模拟孔隙液的碱度是影响球墨铸铁表面钝化膜形成的主要因素;当孔隙液的pH值在12.5以上时,球墨铸铁表面能形成稳定的钝化膜,其成膜时间随孔隙液碱度的升高而降低,且成膜后的球墨铸铁表面腐蚀电位和电荷转移电阻较为稳定;当孔隙液的pH值为11.5时,球墨铸铁表面难以形成钝化膜.本文的研究结果可用于水泥砂浆内衬球墨铸铁管的优化设计.“,”The paper has studied the formation process of passive film on the surface of ductile cast iron in simulated pore solution of cement mortar by using the electrochemical measurement.The influences of the alkalinity of simulated pore solution on the corrosion potential,electrochemical impedance spectroscopy and charge transfer resistance of the ductile cast iron have been analyzed,and the formation condition and time of the passive film on the surface of ductile cast iron have been obtained.Results show that,the alkalinity of solution is a main factor influencing the formation of passivation film on the surface of ductile cast iron,when the pH value of solution is greater than 12.5,the formed passive film is stable,and the formation time of passive film decreases with the increase of pore solution alkalinity,and there exist more stable corrosion potential and charge transfer resistance of ductile cast iron;but when the pH value of solution is 11.5,the passive film can not be formed on the surface of ductile cast iron.This study can be used for the optimum design of cement-mortar-lined ductile cast iron pipe.