Abstract: The steel rebar with low cost and excellent corrosion resistance were prepared by adding trace lanthanum （La） and cerium （Ce） rare earth elements. The effect of rare earth addition on the microstructure and corrosion resistance of corrosion resistant steel was studied by means of electrochemical workstation， X-ray diffraction （XRD） and scanning electron microscope （SEM）. The results show that rare earth elements refine the grain size and promote the transformation of MnS and Al2O3 ·SiO2 composite inclusions with long and irregular shape into spherical inclusions （Ce，La） 2O2S with smaller size and more regular shape. Following the addition of rare earth elements， the corrosion potential of the steel shifts positively， while the corrosion current is reduced. Furthermore， rare earth elements contribute to the reduction of unstable γ-FeOOH in the corrosion products， promoting the formation of more stable α-FeOOH， which enhances the stability， compactness， and adhesion of the rust layer. As the rare earth content increases， the corrosion resistance of the steel gradually improves， with the optimal performance observed in the steel containing 0.01% rare earth elements.

Key words: Rare Earth Alloying, Corrosion Resistant Steel, Inclusion Modification, Corrosive Properties

摘要： 通过添加微量镧（La）和铈（Ce）稀土元素，制备了成本低、耐蚀性优异的钢筋。利用电化学工作站、X射线衍射（XRD）和扫描电子显微镜（SEM）等手段，研究了稀土添加量对耐蚀钢的组织和耐蚀性能的影响。结果表明，稀土元素细化了晶粒尺寸，促使长条状、形状不规则的MnS和Al2O3·SiO2复合型夹杂物转变为尺寸更小、形态更规则的球形夹杂物（Ce，La）2O2S。添加稀土元素后，耐蚀钢的腐蚀电位发生正向移动，降低了腐蚀电流。此外，稀土元素可以使腐蚀产物中不稳定的 γ-FeOOH 含量减少，形成更多稳定的α-FeOOH，增强了锈层的稳定性、致密性和附着能力。随着稀土含量的增加，耐蚀钢的耐腐蚀性能呈现出逐渐提高的趋势，其中，0.01%稀土添加量的耐蚀钢表现出最佳的耐腐蚀性能。

关键词: 稀土合金化, 耐蚀钢, 夹杂物改性, 腐蚀性能