两种船体钢焊接接头耐海水腐蚀性能对比
The Corrosion Behaviors of Welded Joints of 3C Carbon Hull Structural Steels
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摘要: 选择了两种碳素船体钢(经稀土变性处理和未经稀土变性处理的3C钢)和3种常用的焊接材料,加工成6种焊接接头试样,通过室内全浸搅拌挂片试验、间浸挂片试验和恒电位阳极溶解试验,对同一焊接接头不同区域以及不同焊接接头之间腐蚀行为的差异进行了比较,并结合冶金检测结果分析探讨了造成该腐蚀特点的原因。结果表明,对3C钢常用焊接接头而言,均为焊缝区耐海水腐蚀性能最差,其次为母材,热影响区耐蚀性最好;经稀土变性处理后,3C钢不仅钢种本身的耐蚀性得到了提高,而且以该钢为母材的焊接接头的耐蚀性也得到了相应的改善(同种焊接材料相比);无论是普通3C钢还是稀土变性处理3C钢均以J422为焊接材料的接头的耐海水腐蚀性能最好。Abstract: Two kinds of carbon hull structural steels (the 3C steel which is Re-free and the 3C corrosion resistant steel which is modified by Re) and three kinds of welding consumables are selected and made into six kinds of welded joint specimen.The difference of corrosion behaviors of six welded joint specimen and distinct zones of the welded joint specimen have been investigated by means of laboratory stirring immersion test,dry-wet intermittent test and constant potential anodic dissolution test.Furthermore,conbined with the metallurgical analysis,the reason which makes these corrosion results are discussed.The results indicate that the weld zone and base metal show more corrosive than the heat affected zone(HAZ),while the weld zone is easier to corrode than the base metal.Not only is the corrosion resistance of structural steel improved itself with Re additions,but also the corrosion resistance of the steel welded joint is also improved correspondingly (compared to the same welding consumable).For Both the 3C steels which are Re-free and the 3C corrosion resistant steel which is modified by Re,the corrosion resistance of welded joint using J422 consumable is higher than using other two welding consumables.