建筑用耐候钢在含Cl-环境中的腐蚀行为研究

Corrosion Property of Weathering Steel Used for Construction in Environment Including Cl^-

研究了桥梁建筑用耐候钢在含Cl-环境下表面锈层的腐蚀行为。结果表明,耐候钢组织由粒状贝氏体、针状铁素体以及准多边形铁素体组成。材料中的微量合金元素Mn可以降低腐蚀后期晶粒尺寸,促进α-FeOOH和γ-FeOOH相形成,提高材料表面锈层致密度。而Cu主要富集在锈层孔洞和缝隙处,能够改善表面锈层质量,提高耐候钢的抗腐蚀性。

The corrosion property of the weathering steel rust layer used for bridge building in the environment including Cl-was investigated. The results show that the microstructures of the steel are made of granular bainite, needle-like ferrite and quasi-polygonal ferrite. The microalloying element Mn can reduce the grain size of the steel in the later period of corrosion, and promote the formation of α-FeOOH and γ-FeOOH phases, which may improve the density of the rust layer. And the Cu in the steel accumulates in the hole and gap of the rust layer, and can improve the surface quality, and thus increase corrosion resistance of the weathering steel.