采用增重法和电化学方法研究了Q235钢表面环氧粉末涂层在不同含量NaCl溶液（溶液中NaCl质量分数为0，1.0%，3.5%，6.0%，8.5%）中的吸水量和耐腐蚀性能，分析了氯离子对涂层失效的影响。结果表明：随着溶液中氯离子含量的增加，环氧粉末涂层的饱和吸水量减少，达到饱和吸水的时间缩短；氯离子加速了环氧粉末涂层的失效，且溶液中氯离子含量越高，涂层失效越快，界面腐蚀越早发生，金属基体腐蚀越严重。

Water absorption amount and corrosion resistance of epoxy powder coating on surface of Q235 steel in NaCl solution of different contents (mass fractions of NaCl in solution were 0, 1.0%, 3.5%, 6.0%, 8.5%) were studied by weight gain method and electrochemical method. The effect of chloride ion on the failure of the coating was analyzed. The results show that with increasing content of chloride ion in the solution, the saturated water absorption amount decreased, and the time interval for reaching the saturated water abroption was shortened. The chloride ion accelerated the failure of the epoxy powder coating. Moreover, the higher the chloride ion content in the solution was, the faster the coating failed, the earlier the interface corrosion occurred, and the more severe the corrosion of the metal matrix was.