输电塔既有涂层与新涂层受风沙侵蚀的损伤机理  

Damage Mechanism of Existing Coating and New Coating of Transmission Towers Eroded by Wind-blown Sand

作　　者：郝贠洪[1,2] 李洁 刘永利[1,2] HAO Yunhong;LI Jie;LIU Yongli(.1School of Civil Engineering,Inner Mongolia University of Technology,Hohhot 010051;The Inner Mongolia Key Laboratory of Civil Engineering Structure and Mechanics,Inner Mongolia University of Technology,Hohhot 010051)

机构地区：[1]内蒙古工业大学土木工程学院,呼和浩特010051 [2]内蒙古工业大学内蒙古自治区土木工程结构与力学重点实验室,呼和浩特010051

出　　处：《材料导报》2019年第8期1389-1394,共6页Materials Reports

基　　金：国家自然科学基金(11862022; 11162011; 51468049; 11662012);国家电网公司科技项目(GCB51201602754)~~

摘　　要：对输电铁塔杆件新镀锌涂层和既有镀锌涂层进行风沙冲蚀磨损试验,对比分析了两种不同镀锌涂层的冲蚀损伤规律。采用扫描电子显微镜和激光共聚焦显微镜观测两种涂层的不同冲蚀磨损微观形貌,分析了两种涂层材料受风沙冲蚀的损伤机理。研究表明:冲蚀速度越高,两种涂层的冲蚀率越大,且既有涂层的冲蚀率在相同的冲蚀条件下比新镀锌涂层的冲蚀率要高500×10^(-5)～2 750×10^(-5)mg/g;两种涂层在冲蚀角度α为35～37°时出现了最大冲蚀率,分别为2.5×10^(-5)mg/g(新涂层)和0.014 mg/g(既有涂层)。两种涂层在冲蚀角度α=90°时冲蚀率最小,分别为0.5×10^(-5)mg/g(新涂层)和700×10^(-5)mg/g(既有涂层);两种涂层的冲蚀形貌是从低角度的犁沟型冲蚀沟发展到冲蚀沟和冲蚀坑并存,再到高角度仅存的冲蚀坑形貌。风沙流对输电铁塔杆件新镀锌涂层和既有镀锌涂层的冲蚀磨损过程大致相同,既有镀锌涂层的冲蚀坑和带状冲蚀沟比新镀锌涂层更深、更长,且表面更加粗糙。The wind-blown sand erosion and wear tests on the new galvanized coating and existing galvanized coating of transmission tower bar were carried out in this study,and comparative analysis on the erosive damage law of the two types of galvanized coating was conducted as well.Scanning electron microscope and laser scanning confocal microscope were adopted to observe the micro-structures of erosive wear on these two kind of coatings,and analyze their mechanisms of sand erosion and damage.Research results indicated that higher erosion velocity contributed to enlarge the erosion rate of the coatings.Under the same erosion condition,the erosion rate of the existing galvanized coating was 500×10^-5 mg/g to 2 750×10^-5 mg/g higher than that of the new galvanized coating.Whenαwas 35-37°,both of the coatings exhibited the highest rate of erosion,which were 2.5×10^-5 mg/g(new coating)and 0.014 mg/g(existing coating),respectively.Whenα=90°,both of the coatings presented the lowest rate of erosion,which were 0.5×10^-5 mg/g(new coating)and 700×10^-5 mg/g(existing coating),respectively.Erosion morphology of these two coatings developed from the low-angle erosion gullies to the coexistence of erosion gullies and erosion pits,and finally only scour pits remained at the high angle.There were primarily the same erosion and wear process of wind-drift sand on the new galvanized coating and existing galvanizes coating of transmission tower,while existing galvanized coating showed deeper and longer erosion pits and zonal erosion gullies,as well as rougher surface than new galvanized coating.

关 键 词：输电铁塔杆件涂层 风沙环境 冲蚀 损伤机理 

分 类 号：TG174.44[金属学及工艺—金属表面处理]