摘要
为了提高细晶高强钢筋(HRBF500钢筋)的耐蚀性及对应海工混凝土结构的耐久性,在含3.5%NaCl的模拟混凝土孔隙液(SCP溶液)中添加β-甘油磷酸钠(BG),通过动电位极化和交流阻抗谱(EIS)测试研究BG含量对HRBF500钢筋电化学腐蚀行为的影响,通过Mott-Schottky曲线测试研究HRBF500钢筋表面腐蚀产物膜的半导体特性,采用SEM观察钢筋表面的腐蚀形貌,并与普通碳素光圆钢筋(HPB235)作比较。结果发现:BG为阳极型缓蚀剂,有利于钢筋钝化。随着BG含量的增加,HRBF500钢筋的腐蚀电流密度先明显降低后稍有提高,钝化膜的载流子密度减小,阻抗值明显增大。以1.0 g/L BG时的缓蚀效果最佳。不含缓蚀剂时,HPB235钢筋的耐蚀性优于HRBF500钢筋,但1.0 g/L BG缓蚀剂使二者的耐蚀性十分接近。在含氯离子的混凝土环境中,添加合适的缓蚀剂,可以确保HRBF500钢筋的耐久性和安全性,有利于其工程推广应用。
To improve the corrosion resistance of the fine-grained high-strength steel bar(HRBF500 steel bar) and the durability of the corresponding marine concrete structures, sodium β-glycerolphosphate(BG) was added to the simulated concrete pore solution(SCP solution) containing 3.5% NaCl. The effect of BG content on the electrochemical corrosion behavior of HRBF500 steel bar was investigated using potentiodynamic polarization and electrochemical impedance spectroscopy(EIS). Mott-Schottky curves were employed to study the semiconductor characteristics of the corrosion product film on the HRBF500 steel bars' surface. Additionally, the corrosion morphology on the surface of steel bar was observed using scanning electron microscopy(SEM), and it was compared with ordinary carbon plain round steel bar(HPB235). Results showed that BG acted as an anodic corrosion inhibitor, facilitating the passivation of steel reinforcements. With the increase in BG content, the corrosion current density of HRBF500 steel bar initially decreased significantly and then rose slightly. The carrier density of the passivation film reduced, and the impedance value notably increased. The optimal corrosion inhibition effect was observed with 1.0 g/L BG. Without an inhibitor, the corrosion resistance of HPB235 steel bar was superior to that of HRBF500 steel bar. However, the addition of 1.0 g/L BG corrosion inhibitor made their corrosion resistances very similar. By adding an appropriate corrosion inhibitor to concrete environment containing chloride ions, the durability and safety of HRBF500 steel bars could be enhanced, which was advantageous for their application and popularization in engineering.
作者
邵俊杰
林碧兰
陈凌
SHAO Junjie;LIN Bilan;CHEN Ling(School of Material Science and Engineering,Xiamen University of Technology,Xiamen 361024,China)
出处
《材料保护》
CAS
CSCD
2024年第1期88-95,共8页
Materials Protection
基金
福建省自然科学基金项目(2020J01291)资助。
关键词
钢筋
HRBF500
耐蚀性
β-甘油磷酸钠缓蚀剂
模拟混凝土孔隙液
steel bar
HRBF500
corrosion resistance
sodiumβ-glycerolphosphate corrosion inhibitor
simulated concrete pore(SCP)solu-
