NaCl对镀锌钢的腐蚀相当严重，而大气中含有的SO2对该腐蚀过程起到促进作用，因此研究该环境体系下的金属腐蚀行为和机理相当重要。通过采用恒沉积盐下干/湿交替腐蚀的方式，用腐蚀增重、动电位极化曲线、电化学阻抗谱等分析方法，探究镀锌钢在模拟海洋 - 工业大气环境下的腐蚀情况与腐蚀特点。研究结果表明：金属的腐蚀程度随着Cl-浓度的增大而加剧，在干/湿交替腐蚀前期，锌层作为牺牲阳极保护基体，腐蚀产物易分解，腐蚀程度较轻；在腐蚀后期，碳钢开始腐蚀，腐蚀产物为红锈，腐蚀明显加剧，镀锌钢的锌层已失去了阴极保护作用，腐蚀速度随着腐蚀时间的延长而呈幂指数趋势增大。
李 波, 何锦航, 余思伍, 白 洁, 肖仁贵, 仇 伟, 刘孟磊, 彭盛燕, 廖 霞
. 镀锌钢在模拟沿海-工业大气中的腐蚀行为[J]. 材料保护, 2022
, 55(7)
: 128
-136
.
DOI: 10.16577/j.issn.1001-1560.2022.0193
NaCl can cause serious corrosion of galvanized steel, and the SO2 contained in the atmosphere promotes the corrosion process, so it is of great significance to study the corrosion behavior and mechanism of metals in this environmental system. In this work, alternating dry/wet corrosion in case of constant deposition salt was tested to investigate the corrosion condition and corrosion characteristics of galvanized steel in simulated coastal - industrial atmosphere using corrosion weight gain, dynamic potential polarization curves, electrochemical impedance and other analytical methods. Results showed that the corrosion degree increased with the rising of Cl - concentration. In the early stage of corrosion, the zinc layer served as a sacrificial anode to protect the substrate, and corrosion products were easy to decompose, so the corrosion degree was relatively light. In the late stage of corrosion, carbon steel began to corrode, corrosion products were the red rust, the corrosion increased significantly, the galvanized steel lost its cathodic protection previously provided by the zinc layer, and the corrosion rate increased exponentially with the prolonging of the corrosion time.
