PTFE乳液对景观钢结构表面镀层耐蚀性的影响  

Effect of PTFE emulsion on corrosion resistance of surface coating of landscape steel structure

作　　者：周研 罗志峰 秦叔玉 ZHOU Yan;LUO Zhifeng;QIN Shuyu(Jilin University of Architecture and Technology,Changchun 130114,China;Jilin University,Changchun 130012,China)

机构地区：[1]吉林建筑科技学院,吉林长春130114 [2]吉林大学,吉林长春130012

出　　处：《电镀与涂饰》2022年第3期181-186,共6页Electroplating & Finishing

基　　金：吉林省教育厅“十三五”项目(JJKH20190407SK)。

摘　　要：为了提升景观钢结构的耐腐蚀性能,对Q345钢进行了化学镀镍处理,对比了Ni–P合金镀层和镀液中添加不同体积分数的PTFE乳液后得到的Ni–P–PTFE复合镀层的物相组成、元素成分、显微形貌和电化学腐蚀行为。结果表明,Ni–P合金镀层和Ni–P–PTFE复合镀层都主要为非晶态结构,当PTFE乳液的添加量达到5 mL/L及以上时,Ni–P–PTFE复合镀层中会出现一定量的晶态Fe_(3)C和P_(4)S_(3)。相较于Ni–P合金镀层,Ni–P–PTFE复合镀层的腐蚀电位发生正移,腐蚀电流密度减小,阻抗增大,表明Ni–P–PTFE复合镀层的耐腐蚀性能优于Ni–P合金镀层。PTFE乳液添加量为0.2 mL/L时所得Ni–P–PTFE复合镀层的耐蚀性最好,这主要与此时镀层表面较为平整、致密性较好有关。Electroless nickel plating was conducted on Q345 steel,one of the commonly used steels for landscape structures,to improve its corrosion resistance.The phase constitution,elemental composition,micromorphology,and electrochemical corrosion behavior of the Ni-P alloy coating were compared with those of the Ni-P-PTFE composite coatings prepared with different volume fractions of PTFE emulsion in the electroless nickel plating bath.The results showed that,the Ni-P alloy coating and Ni-P-PTFE composite coating are mainly of amorphous structure,but there will be a certain amount of crystalline Fe_(3)C and P_(4)S_(3) in the Ni-P-PTFE composite coatings prepared when the addition of PTFE emulsion is not less than 5 mL/L.As compared with the Ni-P alloy coating,the Ni-P-PTFE composite coating had a more positive corrosion potential,a lower corrosion current density,and a larger impedance,indicating that the corrosion resistance of Ni-P-PTFE composite coating is better than that of the Ni-P alloy coating.The Ni-P-PTFE composite coating prepared with PTFE 0.2 mL/L has the best corrosion resistance,which is mainly due to the smoothness and compactness of its surface.

关 键 词：碳钢 镍-磷合金 聚四氟乙烯颗粒 化学镀 形貌 耐蚀性 

分 类 号：TG335.22[金属学及工艺—金属压力加工]