4种钢在含硫拜耳液中的腐蚀行为

Corrosion behavior of four kinds of steels in sulfide-containing Bayer liquor

通过高温浸泡腐蚀实验、动电位极化曲线法和循环伏安法研究比较16Mn低合金钢、A3碳钢、304L和316L不锈钢在含硫拜耳液中的腐蚀行为。研究结果表明:4种钢在含硫拜耳液中的腐蚀速率从小到大依次为:316L不锈钢、304L不锈钢、A3碳钢和16Mn低合金钢。16Mn低合金钢和A3碳钢在含硫拜耳液中均发生铁的活性溶解使极限电流密度显著增大,与表面形成不稳定的铁硫化物有关,因而耐S2-腐蚀性差。304L和316L能在较低电位下发生钝化,与不锈钢中含Cr,Ni和Mo等合金元素有关,为含硫拜耳液的耐腐蚀性材料。

The corrosion behaviors of 16 Mn low alloy steel, A3 carbon steel, 304 L and 316 L stainless steel in sulfide-containing Bayer liquor were studied by using high-temperature coupon exposure tests, means of anodic polarization curves and cyclic voltammetry. The results indicate that the corrosion rates of the four steels from small to large order are 316 L stainless steel, 304 L stainless steel, A3 carbon steel and 16 Mn low alloy steel. 16 Mn low alloy steel and A3 carbon steel make the limited current density increase for their active dissolution in sulfide-containing Bayer liquor, which is related to the formation of iron sulfide with unprotected structure on the surface. Thus they exhibit poor S2- corrosion resistance. 304 L and 316 L stainless steel can be passive at lower potential, which is related to alloying elements of Cr, Ni and Mo contained in stainless steel. Therefore, they are corrosion resistance materials in sulfide-containing Bayer liquor.