应用动电位极化、电化学阻抗谱、周浸腐蚀试验的方法,研究了HRB400碳钢钢筋和两种Cr合金化的低合金钢筋在0.01mol/L Na HSO3溶液中的腐蚀行为。结果表明,相比HRB400钢筋,Cr合金化钢筋的开路电位明显正移,Cr元素提高了钢的热力学稳定性;随着Cr元素质量分数的增加,钢筋的自腐蚀电流密度减小,极化电阻增大,Cr合金化的钢筋具有相对较小的电化学腐蚀速率;周浸加速腐蚀72 h后,HRB400钢筋和Cr合金化的钢筋均以均匀腐蚀为主,添加Cr元素可以显著降低钢筋的均匀腐蚀速率。
The electrochemical methods of the potentiodynamic polarization, the electrochemical impendence spectroscopy and the dry/wet cycle corrosion test are employed to investigate the corrosion behavior of the Cr modified HRB400 carbon steel rebar in 0.01 mol/L Na HSO3 solution. The open circuit potential of the Cr modified steel shifts in the positive direction as compared with the HRB400 carbon steel; The results of the polarization curve show that the corrosion current density of the Cr modified steel is decreased, the polarization resistance is increased and the corrosion rate is declined. After the dry/wet cycle corrosion test for 72 h, the corrosion morphologies of the HRB400 steel and the Cr modified steel see a uniform corrosion, the addition of the Cr element can significantly reduce the corrosion rate of the HRB400 steel rebar.