热镀锌钢材的电偶腐蚀行为-划痕型缺陷

Wire beam electrode technique for investigating galvanic corrosion behavior of hot-dip galvanized steel-scratch defect

使用锌-碳钢异材质丝束电极技术,模拟并研究了锌/钢电偶腐蚀不同阶段的电位和电流密度的空间分布.结果表明,在锌丝与钢丝面积比为10:1的情况下,锌丝能给钢丝提供足够的阴极保护,且锌丝之间存在明显的电位、电流分布不均现象;钢丝之间也存在电化学参数分布不均现象,而且在受到保护的同时钢丝表面有氢析出.

In order to obtain the spatial distribution and its variation with time during the galvanic corrosion of hot dip galvanized steel if scratches occurred in the zinc coating, the heterogeneous wire beam electrode composed of zinc and mild steel wires was developed, and then the potential and current distributions of this electrode were acquired at different time. The results showed that zinc wires can provide enough cathodic protection to steel wires in seawater when surface area of zinc wires is ten times that of steel wires. The potential and current distributions were inhomogeneous among the zinc wires. The similar heterogeneous phenomenon also presented among the steel wires, and the hydrogen evolution occurred on their surfaces.