Cr对钢耐海水腐蚀性的影响

EFFECT OF CHROMIUM ELEMENT ON CORROSION RESISTANCE OF STEELS IN SEAWATER

获得了 5种含铬低合金钢在海水中暴露 1、2、4、8(7)年的腐蚀数据 ,讨论了Cr对钢耐海水腐蚀性的影响 .铬钢的耐海水腐蚀性不仅与Cr的含量有关 ,还与其他复合合金元素有关 .短期浸泡时 ,钢的耐海水腐蚀性随铬含量 (无其他合金元素复合 )增加而提高 .长期浸泡 ,Cr对钢的耐海水腐蚀性有害 .约 1 %Cr与Mo( Al)复合对钢的耐海水腐蚀性的影响与Cr的影响没有明显差别 .大于 2 %Cr与Mo( Al)复合大幅度提高钢在海水中短期浸泡的耐蚀性 ,并使耐蚀性逆转时间明显推迟 .小于 1 %Cr与Mn Cu、Cu Si V、Ni Cu Si、Ni Mn等复合对钢的耐海水腐蚀性有害 .

Corrosion data of five chromium steels immersed in seawater for 1,2,4,8 years were obtained. Effect of chromium on corrosion resistance of the steels in seawater were evaluated. Corrosion resistance of chromium steels in seawater changes not only with chromium content, but also with other alloying elements combined with Cr. Corrosion resistance of steels in seawater increases with chromium content for a short term immersion. For a long term immersion, chromium decreases corrosion resistance of steels in seawater. The difference between the effect of combined about 1%Cr and Mo(\|Al) on corrosion resistance of steel and the effect of chromium itself is not obvious. Over 2%Cr combined with Mo(\|Al) increases corrosion resistance of steels for a short term immersion by a big margin, and the time that corrosion resistance of chromium steels becomes worse than carbon steel is obviously postponed. While, Cr content less than 1% combined with Mn\|Cu, Cu\|Si\|V, Ni\|Cu\|Si or Ni\|Mn is harmful to corrosion resistance of steel in seawater.