有机/无机缓蚀剂在模拟混凝土孔隙液中对钢筋缓蚀作用对比研究

Comparative Study on Corrosion Inhibition of Organic/Inorganic Inhibitors for Reinforcement in Simulated Concrete Pore Solution

目的检测和评价五种有机/无机缓蚀剂在含3.5%NaCl的模拟混凝土孔隙液(SCP)中对Q235碳钢的缓蚀效果。方法采用动电位极化曲线和电化学交流阻抗谱(EIS)测试方法。结果综合评价后可知,0.0015 mol/L的D-葡萄糖酸钠具有最好的缓蚀效果,浸泡30 d后的Rct可达到282.7^4×104Ω·cm^2,此时的IE为99.99%,对Q235碳钢在模拟海水混凝土孔隙液中的腐蚀具有最佳应用价值。结论各缓蚀剂均存在最优浓度/配比,可使钢筋在含Cl-的SCP溶液中的点蚀电位(Eb)和电荷转移电阻(Rct)显著提高,且缓蚀效率(IE)随浸泡时间的延长而增大。

To evaluate the effects of five organic/inorganic inhibitors on corrosion behavior of Q235 carbon steel in simulated concrete pore solution(SCP)containing 3.5%NaCl through the potentiodynamic polarization curve and electrochemical impedance spectroscopy(EIS).Among of these inhibitors,0.0015 mol/L D-sodium gluconate shows the best IE,i.e.after soaking for 30 days,Rct and IE reach 282.74×10^4Ω·cm^2 and 99.99%,respectively.Therefore,0.0015 mol/L D-sodium gluconate has an optimal application value for Q235 carbon steel in simulated seawater concrete pore solution.Results show that there is the optimal concentration/ratio for each corrosion inhibitor,which significantly improves the pitting potential(Eb)and charge transfer resistance(Rct)of the reinforcement in SCP solution containing Cl-.The corrosion inhibition efficiency(IE)increases with the immersion time.