低合金船体钢点蚀敏感性的研究

Study of pitting sensitivity of low-alloy hull steel

通过极化试验比较了4种含有不同合金元素的低合金钢的点蚀诱发敏感性,并用电子探针对钢中的主要夹杂物及点蚀诱发后的腐蚀形态作了鉴定.结果表明:镍-铬系钢比锰系钢具有更好的耐点蚀性能;点蚀总是从夹杂物与周围钢基体毗邻的界面处开始诱发;含有硫化物的复相夹杂对点蚀的敏感性更强.

Four kinds of low-alloy steels with different alloy elements are selected to compare their sensitivity to pitting by means of polarization test. The EPMA is used to study the main inclusions in the steels and the pitting characters after polarization test. The results show that the sensitivity of the steel with nickel and chromium alloy elements to pitting corrosion is lower than that of the steel with manganese element. It is also found that the pitting easily grows around the rim between inclusion and the matrix of alloy steel. And the multi-phase inclusion with sulfide is more sensitive to pitting corrosion.