Damage Mechanism of Existing Coating and New Coating of Transmission Towers Eroded by Wind-blown Sand
HAO Yunhong1,2, LI Jie1,2, LIU Yongli1,2
1 School of Civil Engineering, Inner Mongolia University of Technology, Hohhot 010051 2 The Inner Mongolia Key Laboratory of Civil Engineering Structure and Mechanics, Inner Mongolia University of Technology, Hohhot 010051
Abstract: 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. When α was 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. When α=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.
郝贠洪, 李洁, 刘永利. 输电塔既有涂层与新涂层受风沙侵蚀的损伤机理[J]. 材料导报, 2019, 33(8): 1389-1394.
HAO Yunhong, LI Jie, LIU Yongli. Damage Mechanism of Existing Coating and New Coating of Transmission Towers Eroded by Wind-blown Sand. Materials Reports, 2019, 33(8): 1389-1394.