Abstract
In this paper, the large area plate of arc-remelted metal of 441 ferritic stainless steel is prepared by multi-arc remelting. The pitting corrosion resistance of base metal and arc-remelted metal is compared through the pitting corrosion immersion test. The microstructure changes of 441 ferritic stainless steel after arc remelting and its influence on pitting corrosion resistance are studied through metallographic structure observation, precipitate analysis and corrosion pit surface observation and analysis. The results show that, compared with the base metal, the grains of arc remelted metal structure grow abnormally and form coarse ferrite columnar structure; there are large particles of carbonitride precipitates of Ti and Nb, and small particles of Laves precipitates containing Nb in the base metal, and the precipitates in the arc remelted metal are smaller and more evenly distributed, most of which are composite precipitates of Nb and Ti. The corrosion rate of base metal is 23.4 g•m^–2•h^–1. After arc remelting, the corrosion rate of metal is 20.88 g m^–2•h^–1, and the pitting corrosion resistance is improved.

Key words
441 ferritic stainless steel, pitting corrosion, arc remelting, precipitate

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