摘要 |
PURPOSE: A martensitic stainless hot rolled steel strip and a manufacturing method thereof are provided to secure the casting safety by preventing a strip breakage and gravity segregation by rapidly cooling the strip when the hot-rolled strip is coiled. CONSTITUTION: A martensitic stainless hot rolled steel strip contains C:0.1~1.5%, Cr:12~15%, Ni: less than 1%, residual Fe, and inevitable impurities. The martensitic stainless hot rolled steel strip is manufactured by a casting process in a twin roll type. An average size of chromium carbide is less than 5μm, and more than 30 chromium carbide per μm^2 formed in a grain boundary. The center gas hole of the martensitic stainless hot rolled steel strip is removed. A method for manufacturing the martensitic stainless hot rolled steel strip is as follows. The molten steel is injected into a pair of rollers, and the martensitic stainless hot rolled steel strip is casted. The casted martensitic stainless hot rolled steel strip is hot-rolled at an in-line rolling mill. The hot-rolled martensitic stainless hot rolled steel strip is coiled, and cooled using a cooling unit(13).
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