(1. 中國石油大學(xué)(華東) 機(jī)電工程學(xué)院，東營 257061；2. 中國海洋大學(xué) 化學(xué)化工學(xué)院，青島 266100)
摘 要: 采用3種不同配置比例的鋅/碳鋼異材質(zhì)絲束電極，模擬鍍鋅層存在不同大小點(diǎn)缺陷時(shí)的熱浸鍍鋼，研究鋅/鋼電偶在不同腐蝕階段的電位和電流密度分布。結(jié)果表明，在鋼絲與鋅絲面積比為1׃120、9׃112和25׃96的3種情況下，鋅絲均能給鋼絲提供足夠的陰極保護(hù)，且鋅絲之間存在明顯的電位、電流分布不均現(xiàn)象，主要陽極區(qū)先隨機(jī)地在鄰近鋼絲的鋅絲區(qū)域內(nèi)轉(zhuǎn)移，而后逐漸向遠(yuǎn)端鋅絲擴(kuò)展；鋼絲之間也存在電化學(xué)參數(shù)分布不均一現(xiàn)象，鋼絲在受到保護(hù)的同時(shí)表面會(huì)有氫原子析出，且隨著陰、陽極面積比的增大，析氫電流密度逐漸減小。
關(guān)鍵字: 絲束電極；鍍鋅層；電偶腐蝕；陰極保護(hù)；氫析出
（1. College of Machinery and Electronic Engineering, China University of Petroleum, Dongying 257061, China;
2. College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China）
Abstract:Three kinds of wire beam electrodes(WBE) composed of zinc and mild steel wires were developed, which were used to simulate hot-dip galvanized steel with spot coating defect at different dimensions, to obtain the spatial distributions of potential and current density and their variations with time during the galvanic corrosion. The results show that the zinc wires within WBEs can provide enough cathodic protection to steel wires after immersed in seawater, with surface area ratio of zinc wires to steel wires as 1:120, 9:112, and 25:96, respectively. The potential and current density distributions are found to be inhomogeneous among zinc wires; firstly, the main anodic areas shift randomly among the zinc wires adjacent to steel wires, then transfer to the direction away from steel wires, and finally occur on the zinc wires farther. The similar heterogeneous phenomenon also appears on steel wires surface on which hydrogen evolution may take part in the cathodic process occurred. Meanwhile, the current density of water molecule reduction reaction decreases with the ratio of the surface area of steel wires to zinc wires increasing.
Key words: wire beam electrode; zinc coating; galvanic corrosion; cathodic protection; hydrogen evolution
