化学镀Ni-P镀层防腐蚀后处理工艺的研究

Post-treatment Processes for Corrosion Resistance on Electroless Ni-P Coating

在钢铁基体上制备化学镀Ni-P镀层后,分别采用γ-氨丙基三乙氧基硅烷(3-APTS),硬脂酸和3-APTS/硬脂酸对镀层进行防腐蚀后处理,利用点滴法、贴滤纸法、接触角测量、盐水浸渍实验法和电化学测试研究了镀层耐蚀性的变化,比较了各工艺的后处理效果。结果表明:3种后处理工艺都能提高化学镀Ni-P镀层的抗氧化性和耐蚀性,经3-APTS/硬脂酸复合处理后的镀层耐蚀性要优于3-APTS和硬脂酸的单一处理,镀层外观都没有明显变化。同时对缓蚀机理进行了分析。

Electroless Ni- P coatings on steel substrate were post- treated with γ- aminopropyltriethoxy silane(3-APTS), stearic acid and compound of the both respectively, and then for the posttreated coatings, the contact angle with pure water was measured and the corrosion performance was evaluated by means of nitric acid spot test and test with filter paper containing K3[Fe(CN)6] solution, immersion test in salt water and electrochemical measurements. The results showed that the post-treatments with the three agents all can enhance the corrosion resistance of the Ni-P coatings;while the appearance of the post- treated coatings was not changed; however among the three agents the compound of 3-APTS/stearic acid is superior to the other two individuals. Besides, the relevant mechanism concerning the inhibition effect of the agents was also discussed.