聚四氟乙烯/Al_(2)O_(3)-13%TiO_(2)复合涂层的制备及耐蚀性研究

Preparation of PTFE/Al_(2)O_(3)-13% TiO_(2) composite coating and its corrosion resistance

首先采用大气等离子喷涂(APS)工艺在N80钢基体上制备Al_(2)O_(3)–13%TiO_(2)(AT13)涂层,采用扫描电子显微镜(SEM)分析了不同功率下所得涂层的表面和截面形貌。然后在AT13涂层上采用溶胶−凝胶法制备聚四氟乙烯(PTFE)涂层。采用接触角测量仪和电化学工作站分别对涂层的水接触角及耐蚀性进行表征。结果表明,等离子喷涂的AT13涂层具有典型的层状结构,40 kW和44 kW功率下喷涂的AT13涂层的表面粗糙度分别为4.210μm和3.992μm,孔隙率分别为7.673%和4.295%,水接触角分别为30.2°和47.9°,对应的PTFE/AT13复合涂层的水接触角为130.0°和139.1°。与AT13涂层相比,PTFE/AT13复合涂层在3.5%NaCl溶液中的腐蚀电位正移,腐蚀电流密度降低,表现出更优的耐蚀性。

Al_(2)O_(3)–13% TiO_(2)(AT13)coatings were prepared on N80 pipeline steel by atmospheric plasma spraying(APS)at different powers,and their surface and cross-sectional morphologies were analyzed by scanning electron microscopy(SEM).A polytetrafluoroethylene(PTFE)coating was prepared on the AT13 coatings by sol–gel method.The water contact angle and corrosion resistance of the coatings were examined by using contact angle meter and electrochemical workstation,respectively.The results showed that the plasma-sprayed AT13 coating had a typical layered structure.The surface roughness,porosity,and water contact angle were 4.210μm,7.673%,and 30.2°respectively for the AT13 coating sprayed at 40 kW and were 3.992μm,4.295%,and 47.9°respectively for that sprayed at 44 kW.The water contact angles of PTFE/AT13 composite coatings prepared from the AT13 coatings sprayed at 40 kW and 44 kW were 130.0°and 139.1°,respectively.As compared with the AT13 coating,the PTFE/AT13 composite coating featured a more positive corrosion potential and a lower corrosion current density,showing better corrosion resistance.