非金属夹杂物对不锈钢耐点蚀性能影响的综述

摘要：首先，总结了3种常用的非金属夹杂物对不锈钢耐点蚀性能影响的研究方法，即原位腐蚀观察、微区电化学法、原子力显微镜。其次，总结了硫化物、氧化物、稀土夹杂物3种不同类型夹杂物对不锈钢耐腐蚀性能影响。随着硫化物含量的增多，不锈钢的耐点蚀性能会下降；对于氧化物的影响，目前的研究集中在氧化物的成分对不锈钢耐点蚀性能的影响。不同成分的夹杂物对不锈钢耐点蚀性能的影响机制还不是很清楚；稀土夹杂物对不锈钢点蚀的影响主要与稀土对不锈钢中夹杂物改性有关。而后，汇总了目前提出的夹杂物对不锈钢耐点蚀性能影响的机制，即贫Cr区机制、微缝隙机制、活性机制。贫Cr区机制主要用于解释硫化物引起的点蚀，后2种主要用于解释氧化物引起的点蚀。最后，提出了夹杂物控制提升不锈钢耐点蚀性能的展望。

Review on effect of non metallic inclusions on pitting corrosion resistance of stainless steel

Firstly, three commonly used research methods of the influence of non metallic inclusions on the pitting corrosion resistance of stainless steel were summarized, including in situ corrosion observation, micro area electrochemistry method, and atomic force microscopy. Secondly, the influence of sulfide, oxide, and rare earth inclusions on corrosion resistance of stainless steel were introduced. The larger number of sulfides in stainless steels decreased the pitting corrosion resistance of stainless steel. For oxide inclusions, the previous studies mainly focused on the influence of oxide composition on the pitting corrosion resistance of stainless steel, whose influence mechanism was still unclear. The influence of rare earth inclusions on the pitting corrosion of stainless steel was mainly related to the modification of inclusions in stainless steel by rare earths. Then, the proposed influence mechanisms of inclusions on the pitting corrosion resistance of stainless steel were summarized, including the mechanism of the poor Cr zone, the mechanism of micro crevices, and the mechanism of inclusion activity. The Cr poor zone mechanism was mainly used to explain the pitting corrosion induced by sulfides, and the other two were mainly used to explain the pitting corrosion induced by oxides. Finally, the prospect of improving the pitting corrosion resistance of stainless steel based on control of inclusions was proposed.