稀土铈对化学镀复合镀Ni-P-PTFE镀层耐蚀性能的影响

Effect of Cerium Concentration on the Anticorrosive Property of Electroless Ni-P-PTFE Composite Coating

为了进一步提高化学镀Ni-P-PTFE复合镀层的耐蚀性能,采用在化学镀液中添加稀土铈的方法在45号碳钢试片表面制备了稀土铈Ni-P-PTFE复合镀层。用扫描电镜观察了镀层的表面形貌,并研究了稀土铈浓度对镀层中PTFE含量的影响,通过浸泡失重法分别研究了在3.5%NaCl和3.5%NaOH溶液中稀土铈浓度对镀层耐蚀性能的影响。结果表明:适量稀土铈的加入提高了镀层中PTFE的含量,降低了镀层的腐蚀速率,提高了复合镀层的耐蚀性能,在铈质量浓度为0.02 g/L时,在3.5%NaCl和3.5%NaOH溶液中镀层的腐蚀速率分别为0.402 mg/cm2和0.235 mg/cm2。

In order to improve the anticorrosion of elelctroless Ni-P-FTFE composite coating, electroless Ni-P-PTFE composite coatings were prepared on 45＂ carbon steel specimen in chemical plating solution with addition of rare earth cerium （Ce）. Surface morphology of the coatings was observed by scanning electron microscope （SEM）. Effect of cerium concentration on PTFE content of the coatings was investigated. And effect of cerium concentration on corrosion behavior of the composite coatings was evaluated by immersion test with 3.5% NaC1 and 3.5% NaOH solutions respectively. The results obtained indicate that proper addition of cerium into the bath increases the PTFE content of the coatings, decreases the corrosion rate, improving the anticorrosive property of the coatings. Corrosion rates of the composite coatings in 3.5% NaC1 and 3.5% NaOH are 0. 402 mg/cm^2 and O. 235 mg/cm^2 in the cerium concentration of O. 02 g/L, respectively.