B-containing hot-rolled steel plate/strip with sulfuric acid dew point corrosion resistance and manufacturing method thereof

Abstract

The invention discloses a B-containing hot-rolled steel plate / strip with sulfuric acid dew point corrosion resistance and a manufacturing method thereof. In the method, microalloy elements such as Cr,Ti, Sb and Cu and an element B are selectively added; in the smelting process, the alkalinity of slag, the type and melting point of inclusions in steel, the content of free oxygen in molten steel and the content of acid-soluble aluminum Als are controlled; double-roller thin-strip continuous casting is adopted for casting a cast strip, and the cast strip enters a lower closed chamber with a non-oxidizing atmosphere after being discharged out of crystallization rollers and enters an online rolling mill under the closed condition to be subjected to hot rolling; and a gas atomization cooling mode is adopted for cooling strip steel after rolling, and finally the strip steel is coiled. The steel strip produced by the method can be widely applied to the field of products with use environmentsrequiring sulfuric acid dew point corrosion resistance, such as tobacco baking equipment and air preheater heat exchange elements, conveying pipes, flue and chimney manufacturing structural parts andboiler preheater and economizer equipment in the industries of petroleum, chemical engineering, electric power, metallurgy and the like.

Description

technical field [0001] The invention belongs to the continuous casting process in the metallurgical industry, and in particular relates to a B-containing hot-rolled steel plate / strip for sulfuric acid dew point corrosion resistance and a manufacturing method thereof. Background technique [0002] Most of the traditional thin strip steel is produced by multi-pass continuous rolling of the slab with a thickness of 70-200mm. The traditional hot rolling process is: continuous casting + slab reheating and heat preservation + rough rolling + finishing rolling + cooling + Coiling, that is, firstly obtain a cast slab with a thickness of about 200mm through continuous casting, reheat the cast slab and keep it warm, then perform rough rolling and finish rolling to obtain a steel strip with a thickness generally greater than 2mm, and finally process the steel strip Laminar cooling and coiling complete the whole hot rolling production process. If it is necessary to produce a steel stri...

AI Technical Summary

Problems solved by technology

At the same time, the contact of high-temperature strip steel with cooling water will cause many problems: first, water spots (rust spots) will be formed on the surface of the strip steel, which will affect the surface quality; second, the cooling water used for laminar flow cooling or spray cooling It is easy to cause uneven local cooling on the surface of the strip, resulting in uneven microstructure inside the strip, resulting in uneven properties of the strip and affecting product quality; third, uneven local cooling on the surface of the strip will cause deterioration of the shape of the strip , affecting the shape quality

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