| As the austenitic stainless steel is expensive and nickel resources deficiency, therefore, no ickel and low nickel stainless steel obtained the many national developments and the applied research vigorously. In this paper, the representative of 400 series stainless steels 430,410 S,409L, combined with its microstructure and composition, focus on the corrosion resistance of its hot-rolled sheet and compared with the austenitic stainless steels 304. The anticorrosion performance should be the stainless steel first operational performance, its test and the contrast must achieve as far as possible widely, and has the representation. This paper is to study the general corrosion of 400 series stainless steel(10 medium), also examined its localized corrosion (intergranular corrosion and pitting). To further enhance the quality of three types of stainless steel products and improving process parameters provide a theoretical basis for the development of ferritic stainless steel to provide experimental data and the production.The results showed that the corrosion rate by soaking of three types of ferritic stainless steel was worse than the corrosion resistance of 304 stainless steel.This indicated that the austenite the corrosion resistance must surpass the ferrite,304 of high Cr and Ni could enhance the material corrosion resistance. It also determines the scope of use of ferrite limitations, so to enhance the ferritic stainless steel corrosion resistance, then the application will have more space.Ferritic stainless steel in sulfuric acid and hydrochloric acid corrosion resistance from strong to weak order is:430,409 L,410S, in the mixed acid corrosion resistance from strong to weak order is:409L,410S,430, are resists corrosion in the sodium hydroxide. The results showed Cr content in ferritic stainless steel affected the main elements of content, the stronger the higher the corrosion resistance, ferritic stainless steel of impurities, especially C would reduce the corrosion resistance of stainless steel.Reaction from the media after the nature and the color of the solution were:stainless steel in sulfuric acid, hydrochloric acid was mainly of hydrogen depolarization corrosion, hydrogen would be released during the reaction, formation of iron ions (Fe2+);occurred in the sodium hydroxide solution mainly the oxygen depolarized corrosion; occurred in the mixed acid is double-accelerated corrosion of the anode and cathode.Acid in sodium hydroxide and mixed to generate a ferric ion (Fe3+).The results showed that:The corrosion weight loss curves of test steel There are four main types:oblique line type; parabola; (almost no corrosion) close to the horizontal axis of the horizontal line; approximate level line.Tendency to intergranular corrosion of stainless steel from small to big:304,430,409 L, 410S.Compared with the austenitic stainless steels, ferritic stainless greater tendency to intergranular corrosion. Higher Cr content and lower carbon content can increase the resistance to intergranular corrosion of stainless steel capacity, Ti elements can be added to improve resistance to intergranular corrosion of stainless steel capacity.From pitting macroscopic appearance and corrosion rate generalized analysis:Although the austenite stainless steel 304 bear the general corrosion compared to the ferritic stainless steel, but the ferritic stainless steel 304 bears the pitting compared to the austenite stainless steel. The ferrite bears the pitting ability weakly from to:410S,409L,410,430.in the 410S martensite enhanced it to bear the pitting ability,430 excessively many carbide bandings decreased its it to bear the pitting ability seriously.Immersion corrosion on the macro morphology, SEM and EPMA Analysis of ferrite in all of etching for the full corrosion. Stainless steel in hot rolled bands formed during the corrosion process of the Organization will happen stratified sample manipulation to corrosion, the corrosion layers layered microstructure of the section width of its line width.410S and 430 in 10% H2SO4 and 10% HCl solution is easy to form cross-section of pitting.430 in the mixed acid solution and the sample post-stratified corrosion cracking significantly, indicating a mixed acid on destructive and high carbon stainless steel is very content on the adverse effects of corrosion resistance of stainless steel.
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