304 不锈钢在氯化钠介质中点蚀缓蚀剂的研究

目的研究钼酸钠、葡萄糖酸钠及其复配物在氯化钠介质中,对304不锈钢点蚀的缓蚀作用。方法对钼酸钠、葡萄糖酸钠按不同配比进行复配得到不同缓蚀剂,采用极化曲线法分别测试在这几种缓蚀剂存在的条件下,304不锈钢在3.5%(质量分数,后同)NaCl溶液中的点蚀电位。结果单组分的钼酸钠、葡萄糖酸钠对在3.5%NaCl介质中的304不锈钢点蚀有一定的抑制作用,且两种缓蚀剂有明显的协同缓蚀效应。结论当复配缓蚀剂配比为c(钼酸钠)∶c(葡萄糖酸钠)=2∶1时,其缓蚀效果达到最佳,点蚀电位为436 mV。

Study on Inhibitors for the Pitting Corrosion of 304 Stainless Steel in Sodium Chloride Medium

Objective To investigate the inhibition effect of sodium molybdate, sodium gluconaten and their mixtures on 304 stainless steel in sodium chloride medium. Methods Sodium molybdate and sodium gluconate were compounded at different proportions to obtain different complex inhibitors, and then electrochemical polarization curve was used to test the pitting potential of 304 stainless steel in 3. 5% NaCl solution in the presence of these types of corrosion inhibitors. Results One-component sodium molybdate and sodium gluconate exhibited certain inhibitory effects for pitting on 304 stainless steel in 3. 5% NaCl medium, and there was significant synergistic inhibition effect between these two corrosion inhibitors. Conclusion The best ratio of the compounded inhibitor was 2:1 (27 mmol/ L sodium molybdate and 13 mmol/ L sodium gluconaten), and the pitting potential could reach 436 mV.