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应用定向凝固技术制备了Ｃｒ系白口铸铁，采用萃取法制备碳化物试样，用失重法测得腐蚀速率，并通过电化学法探讨Ｃｒ系白口铸铁在腐蚀介质中的相间腐蚀机理，结果表明：（１）Ｃｒ系白口铸铁在腐蚀介质中存在严重的相间腐蚀，相间腐蚀失重率占合金总腐蚀失重率的一半以上；（２）碳化物的电化学行为不同于合金和基体，一直处于自钝化状态，Ｍ７Ｃ３型碳化物比Ｍ３Ｃ型更耐蚀、更稳定；（３）碳化物与基体两相间的腐蚀电位差是相间腐蚀的驱动力，在此腐蚀过程中，碳化物被保护，基体被加速腐蚀，提高基体的腐蚀电位，不仅可以降低相间腐蚀速率，而且能够大幅度提高 Ｃｒ系白口铸铁的耐蚀性。
Cr-based white cast iron was prepared by directional solidification technique. The carbide samples were prepared by extraction method. The corrosion rate was measured by weight loss method. The mechanism of interphase corrosion of Cr-based white cast iron in corrosive medium was discussed by electrochemical method. The results show that: (1) Cr-based white cast iron has serious interphase corrosion in the corrosive medium, and the interphase corrosion weight loss rate accounts for more than half of the total corrosion weight loss rate of the alloy. (2) The electrochemical behavior of carbides is different from that of the alloy and matrix In the self-passivation state, M7C3 type carbide is more corrosion-resistant and more stable than M3C type. (3) Corrosion potential difference between two phases of carbide and matrix is the driving force of interphase corrosion. In this corrosion process, carbide is protected , The matrix is accelerated corrosion, improve the corrosion potential of the substrate, not only can reduce the phase corrosion rate, but also can greatly improve the corrosion resistance of white cast iron Cr Department.