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This article describes the phosphorus chemical equipment ferritic stainless Cr30Mo development, including the design of the chemical composition of steel, smelting, casting and heat treatment process design. Using optical microscopy, X-ray diffraction, electron probe microanalysis tools and mechanical test, electrochemical test, corrosion wear test, the concept of field trials and other coupon test methods, observation and analysis of the microstructure of the steel to study the properties of the steel, and stainless steel abrasion mechanism of brittle mechanism, micro issues such as co-Elysees for a more comprehensive discussion. Electrochemical through laboratory tests, corrosion and wear tests and phosphate fertilizer plant on-site analysis of coupon test results indicate that: Cr30Mo high chromium ferritic stainless steel with a low carbon, ensure its phosphate slurry has sufficient corrosion resistance: Cr30Mo of (Fe, Cr) 2 3C 6 , (Fe, Cr) 7 C 3 , Mo < sub> 2 C, such as the hard carbide particles diffusion from the substrate can increase the precipitation of hardness and wear resistance of steel, so that the slurry in phosphoric acid steel has good abrasion effect. Different carbon content ferritic stainless steel Cr30Mo organizational structure, mechanical properties, abrasion performance and fracture morphology of the analysis that the carbon content increases, favorable hardness of steel, but the toughness, abrasion sex at a disadvantage. With the increased carbon content, germination of grain boundary carbides, extended reticular, castings brittle cleavage fracture developed by the intergranular fracture, while ferritic stainless steels to intergranular corrosion tendency increases. Studies of niobium, vanadium, titanium, rare earth elements on stainless steel structure, mechanical properties, abrasion performance, and brittle, the results showed that micro-fit I of ferritic stainless steel to improve corrosion resistance, an effective way to reduce brittleness. Wherein the rare earth to purify the ferrite grain boundary, and play a modifier role in refining the ferrite grains to improve the toughness of steel; niobium, vanadium, titanium and carbon steel can combine to reduce the loss of chromium solution , thus avoiding intergranular corrosion, and fine micro-precipitation of alloy carbides to improve the wear resistance of stainless steel. Moreover, since the small size of micro-alloy carbides, up to 2 ~ 3nm, the micro-crack propagation effects have certain constraints. In order to comprehensively improve Cr30Mo ferritic stainless steel performance, give full play to the role of micro-alloyed stainless steel, stainless steel heat treatment process for the study and make high temperature solution treatment, controlled cooling measures.
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