纳米Al2O3封孔对电弧喷涂3Cr13涂层耐腐蚀性能的影响
Influence of Nano-Al2O3 Sealing on Corrosion Resistance of3Cr13Coatings Prepared by Arc Spraying
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摘要: 采用电弧喷涂技术在Q235钢基体上制备了约150μm 厚的3Cr13涂层,并采用3种添加不同含量的纳米 Al2O3异丙醇溶液的有机硅树脂对其进行封孔处理,利用光学显微镜(OM)、扫描电镜(SEM)和X射线衍射仪(XRD)对涂层的微观组织和物相组成进行分析,采用全浸泡腐蚀、乙酸盐雾腐蚀以及电化学腐蚀试验研究了未封孔及封孔涂层的耐腐蚀性能。结果表明:3Cr13涂层的物相组成主要为α-Fe(Cr)和Cr2O3,涂层为典型的层状堆积结构,孔隙率约为11%;涂层封孔后的耐腐蚀性能明显优于未封孔涂层的,而且添加质量分数为6%的纳米 Al2O3异丙醇溶液的有机硅封孔剂对3Cr13涂层耐腐蚀性能的提高最为显著。Abstract: 3Cr13coatings were fabricated on Q235steel substrate with thickness of about 150μm by arcspraying,and then the coatings were sealed by three different sealing reagents which were silicone resins withdifferent contents of nano-Al2O3isopropanol.The morphologies and phases of the coatings were analyzed by opticalmicroscopy(OM),scanning electron microscopy(SEM)and X-ray diffractionmeter(XRD).The corrosion resistanceof the coatings was evaluated by full immersion corrosion test,acetic acid salt spray corrosion test andelectrochemical corrosion test.The results show that the main phases of the 3Cr13coating wereα-Fe(Cr)andCr2O3,and the coating was typical layered accumulation structure with porosity of 11%.The corrosion resistance ofthe sealed-coatings was obviously better than that of the unsealed-coating.Moreover,sealing reagent of siliconeresin added 6% nano-Al2O3isopropanol improved the corrosion resistance of the coatings most significantly.