| 摘要: |
| 开发一种新型耐候钢表面锈层稳定化处理剂，促进锈层的快速生长和稳定。以 Q420NH 耐候钢为基材，水性丙烯酸树脂为成膜物，加入两类添加剂——稳定剂(钼酸钠、磷酸钾、硝酸钠)和羟基氧化铁，制备出稳定化处理剂，涂刷于耐候钢的表面，在盐雾环境中研究锈层的生成过程。结果表明，水性丙烯酸树脂具有一定的氧气和水渗透性，适合作为稳定化处理的成膜物。在 90 d 的盐雾试验中，锈层厚度随盐雾时间的增长而不断增加，并且稳定化处理后试样的锈层厚度大于裸钢的锈层厚度。XRD 结果显示，稳定化处理不改变耐候钢锈层的成分，Q420NH 裸钢和稳定化处理的耐候钢的锈层均主要由 Fe3O4、 γ-FeOOH、α-FeOOH、β-FeOOH 组成。SEM 和截面 Raman 光谱结果表明，稳定化处理的试样锈层中保护性的 α-FeOOH 相分布更加广泛。EDS 结果证明 Cr、Cu 合金元素在锈层中富集，电化学阻抗谱说明稳定化处理后的试样具有更佳的耐腐蚀性能。 稳定化处理技术促进了耐候钢表面保护性锈层的生长，缩短了稳定化进程，提高了锈层的保护性能。 |
| 关键词: 耐候钢 稳定化处理 锈层 耐蚀性 盐雾 |
| DOI：10.11933/j.issn.1007-9289.20210510001 |
| 分类号:TG174 |
| 基金项目:国家自然科学基金青年基金(51901015)、海洋装备用金属材料及其应用国家重点实验室和中央高校基本科研业务费(FRF-BD-20-28A2)资助项目 |
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| Stabilization Treatment and Growth Mechanism of Rust Layers on Weathering Steel Surface |
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Ma Lingwei1, Lu Taoli1, Zhang Dawei1, Lu Lin1,2
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1.Institute for Advanced Materials & Technology, University of Science and Technology Beijing, Beijing 100083 , China;2.State Key Laboratory of Metal Material for Marine Equipment and Application, Anshan 114000 , China
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| Abstract: |
| A new stabilization treatment method is developed for the rust layers on weathering steel surface to promote the growth and stability of rust layers. Using Q420NH weathering steel as the substrate material and water-based acrylic resin as the film forming material, two kinds of additives, i.e. stabilizers (Na2MoO4, K3PO4, NaNO3) and α-FeOOH, are added into acrylic resin to prepare the stabilization treatment agent. The formation process of rust layers is investigated during salt spraying. The water-based acrylic resin has good oxygen and water permeability, making it suitable as the stabilization coating. The thickness of rust layer increases with the increase of salt spray time in 90 d , and the rust layer thickness of the stabilized substrate is higher than that of the bare Q420NH steel. X-ray diffraction (XRD) results show that the composition of the rust layer of weathering steel doesn’t change by stabilization treatment, mainly composing of Fe3O4, γ-FeOOH, α-FeOOH, β-FeOOH. Scanning electron microscopy (SEM) and cross-section Raman spectroscopy results indicate that the protective α-FeOOH phase is distributed more widely in the rust layer of the stabilized weathering steel. Energy dispersive spectroscopy (EDS) analysis proves the enrichment of Cr and Cu elements in the rust layer, and electrochemical impedance spectroscopy (EIS) indicated that the stabilized steel has better corrosion resistance property. The stabilization treatment promotes the growth of protective rust layer on the surface of Q420NH weathering steel, which accelerates the stabilization process and improves the protection performance of the rust layer. |
| Key words: weathering steel stabilization treatment rust layer corrosion resistance salt spray |
