模拟酸雨溶液中温度对桥梁索缆镀锌钢丝腐蚀行为影响

Effect of Temperature on Corrosion Behavior of Galvanized Steel Bridge Wires in Simulated Acid Rain

采用Tafel直线外推法、交流阻抗和加速腐蚀试验,研究了拉伸应力作用下高强度镀锌钢丝在不同温度的模拟酸雨溶液中的腐蚀行为,表征其腐蚀前后形貌.结果表明:1100 MPa拉伸应力作用下镀锌钢丝于60℃模拟酸雨溶液中的腐蚀速率为27.6μA/cm2,较室温下腐蚀速率增加31%;腐蚀产物由多孔膜状变为颗粒状堆积于微孔处;1100 MPa拉伸应力作用下镀锌钢丝于50℃盐雾腐蚀试验环境中的腐蚀速率为4.3 mg/dm2.d,较35℃时增加19%.

Corrosion behavior of high strength galvanized steel wires under certain tensile stress was studied at different temperatures in a simulated acid rain by Tafel linear extrapolation, EIS and accelerated corrosion test. Morphologies of the steel wires after corrosion in the simulated acid rain were characterized by SEM. Results showed that corrosion current density of the steel wire under 1100 MPa tensile stress in simulated acid rain at 60℃ was 27.6 μA/cm^2 ,had an increase of 31% in conrparison with that at room temperature. With increasing of temperature, white grainula-like corrosion product formed in the region of micro pores on the steel wire surface, while at room temperature a white film covered the steel wire. Accelerated corrosion test results showed that the corrosion rate of the steel wire was 4.3 mg/dm^2· d in acid fog at 50℃ ,which is 19% higher than that corroded at 35℃.