输电铁塔有机防护涂层的人工老化行为  

Artificial aging behavior of organic protective coatings on transmission towers

作　　者：赵鹏[1] 王斌[2] 吕志文 郑中原[1] 张胜寒[3] 郝春艳[1] 梁可心[3] ZHAO Peng;WANG Bin;LYU Zhiwen;ZHENG Zhongyuan;ZHANG Shenghan;HAO Chunyan;LIANG Kexin(State Grid Tianjin Electric Power Research Institute,Tianjin 300384,China;Tianjin Electric Power Transmission and Transformation Engineering Co.,Ltd.,Tianjin 300161,China;Department of Environment Science and Engineering,North China Electric Power University,Baoding 071003,China)

机构地区：[1]国网天津市电力公司电力科学研究院,天津300384 [2]国网天津市电力公司,天津300010 [3]华北电力大学环境科学与工程系,河北保定071003

出　　处：《电镀与涂饰》2021年第2期142-150,共9页Electroplating & Finishing

基　　金：国网天津市电力公司科技项目(KJ19-1-15)“输电铁塔、壳体涂层腐蚀破损质量检验指标体系建设与应用”。

摘　　要：为了预测输电铁塔有机涂层的使用寿命,达到对其长期保护的目的,研究了不同周期人工加速老化试验中复合涂层(环氧底漆+环氧云铁中间漆+丙烯酸聚氨酯面漆)样本的外观形貌、附着力、红外光谱和孔隙率的变化,建立了附着力−老化时间、孔隙率−老化时间、官能团指数−老化时间等数学模型。结果表明:氙灯加速老化时间12~15 d为涂层老化的重要节点,其间涂层粉化和开裂程度从轻微变中等;附着力随时间推移而先增大后减小;在12~36 d,孔隙率随老化时间延长呈指数式增长;红外光谱官能团指数在12 d内的变化速率明显增大,老化时间与羰基指数(OI)、氨基指数(NI)、环氧基指数(CI)的数量关系均可用同一类型的方程拟合,相关性较好。在实验初期,漆膜的NI随老化时间的延长而急剧增大,而OI的增加较为缓慢,表明丙烯酸聚氨酯面漆中的氨基官能团对老化更为敏感,老化更快。当丙烯酸聚氨酯面漆的NI增大到接近漆膜失效时的值时,环氧中间漆的CI开始增大,表明中间漆开始老化。To predict the lifetime of the coating on transmission tower for its long-term protection,the variation of the morphology,adhesion,infrared spectrum,and porosity of a coating system comprising epoxy primer,epoxy MIO(micaceous iron oxide)midcoat,and acrylic polyurethane topcoat in different periods of artificial accelerated aging test was evaluated.Some mathematical models representing the correlation of adhesion strength,porosity,and functional group indexes with aging time were established.The results showed that the period of the 12th day to the 15th day is important for accelerated aging of the coating under the irradiation of xenon lamp,during which the degree of chalking and cracking of the coating changes from slight to moderate.The adhesion strength of coating was increased initially and then decreased with the extending of aging time.From the 12th day to the 36th day,the porosity was increased exponentially with the extending of aging time.The change rates of the functional group indexes calculated based on the infrared spectra within 12 days of aging were obviously increased.The quantitative correlation of the carbonyl index(OI),amino index(NI),and epoxy index(CI)with aging time can be well fitted by the same type of equation.At the beginning of aging test,the NI was increased rapidly with the extending of aging time,while the OI was increased slowly,indicating that the amino groups in the acrylic polyurethane topcoat is more sensitive to aging with a faster aging rate.Once the NI of the acrylic polyurethane topcoat is increased to approach the value when the coating fails,the CI of the epoxy midcoat begins to increase,indicating the aging of midcoat begins.

关 键 词：输电铁塔 涂层 附着力 孔隙率 老化评价 寿命预测 数学模型 

分 类 号：TG172[金属学及工艺—金属表面处理] TG178[金属学及工艺—金属学]