316L不锈钢焊缝联合防护技术研究

利用阴极保护和涂层相结合的联合保护技术提高316L不锈钢焊缝的耐腐蚀性能.通过测量试样的阴极极化曲线,分析了涂层和阴极保护之间的相容性;通过测量带有涂层的焊缝附近的极化曲线,确定了其自腐蚀电位;通过测量焊件不同区域的交流阻抗Bode图,并利用相关计算方法得出各区域的最佳保护电位;最后,利用保护度计算公式对焊件三区联合保护效果进行比较分析.结果表明:环氧煤沥青涂层与阴极保护之间具有良好的相容性,带涂层的不锈钢焊缝在阴极最佳保护电位下,腐蚀速率大大降低.因此,联合保护能够使不锈钢焊缝区达到很高的保护度.

Study About Combined Protection of 316L Stainless Steel Welding

To improve thecorrosion resistance of 316L stainless steel welding,combined protection which involvedcathodic protection and coating protection was applied to the sample.The compatibility between epoxy coal tar coating and cathodic protection was analyzed by measuring cathodic polarization curves.The corrosion potential was obtained by measuring polarization curvesaround the stainless steel welding.The optimum protective potential was obtained by using corrosion correlation calculation methods to measurethe electrochemical impedance spectroscopy at different welding zones.Finally,a comparative analysis was conducted on the effect of combined protection at different welding zones.The results show that great compatibility between epoxy coal tar coating and cathodic protection exists.The optimum protection potential of the coating sample can obviously reduce the corrosion rate in cathodic protection system.Therefore,the combined protection can guarantee a great protection degree.