目的 研究烧结NdFeB材料镀层失效的问题。方法 通过SEM和电化学的测试方法，包括极化曲线、交流阻抗和零电荷电势等确定失效的主要原因是镀层内部NdFeB的腐蚀，降低了镀层结合力。结果 植酸衍生物可以有效抑制镀层内部的腐蚀。吸附能 为27.93 kJ/mol，表明这种吸附是以物理吸附为主，化学吸附为辅。结论 缓蚀作用机制主要是植酸衍生物分子吸附在NdFeB表面，阻止了腐蚀的发生。

The work aims to study failure of coating on sintered NdFeB. Aided by SEM and electrochemical test methods including polarization curves, AC impedance and zero charge potential, main reason was testified to be NdFeB corrosion inside the coating, which reduced the coating adhesion. Phytic acid derivatives could efficiently inhibit corrosion inside the coating. The was 27.93 kJ/mol. The was mainly physical adsorption and partly chemical adsorption. The corrosion inhibition mechanism is the adsorption of phytic acid derivatives on NdFeB, which prevents the occurrence of corrosion.