海水飞溅区含镍钢的锈层及耐蚀性研究

Rust Layer and Corrosion Resistance of Steels Containing Ni in Marine Splash Zone

通过海水飞溅区暴露实验,获得了两种含镍钢和碳钢3 a的腐蚀结果。采用X射线衍射(XRD)和电子探针显微分析(EPMA)技术,研究了含镍钢飞溅区锈层的特性,讨论了Ni对钢飞溅区锈层及耐蚀性的影响。结果表明,添加2%~3%Ni,使钢锈层中的裂纹和孔洞减小,锈层的致密度提高;外锈层中的α-FeOOH的含量增加。2%~3%Ni的加入有利于盐分中的Na^+和Mg^(2+)向锈层和钢基体界面渗透,对Cl^-的渗透有抑制作用。添加3%Ni,使钢的蚀孔中的Cl^-富集程度显著降低。加入2%~3%Ni能大幅度提高钢在飞溅区的耐蚀性。

Corrosion results of 2 types of steels containing Ni and carbon steel for 3 a were obtained by being exposed in the marine splash zone. Character of the rust layer and corrosion resistance of steels containing Ni were studied through X-ray diffraction （XRD） and electron probe microanalysis （EP- MA）, meanwhile, effect of Ni on the rust layer and corrosion resistance of the steels exposed to splash zone was discussed. The results indicated： by adding 2%-3%Ni, the cracks and holes in the rust layer were reduced and the density of the rust layer were improved, meanwhile, the mFeOOH contents in the outer rust layer were raise. Addition of 2%-3%Ni to the steels was beneficial to the penetration of Na＋ and Mg＋ of the salts to the rust layer and interface with the steel substrate while inhibiting the penetration of CI . When 3% Ni was added, enrichment degree of CI in the pits of the steel was significantly de- creased. Corrosion resistance of the steels in splash zone was dramatically improved by adding 2% to 3% Ni.