MARTENSITIC STAINLESS STEEL PRODUCED BY A TWIN ROLL STRIP CASTING PROCESS AND METHOD FOR MANUFACTURING SAME

摘要

The present invention relates to a martensitic stainless steel produced by a twin roll strip casting process and a method for manufacturing the same. The key technical features of the present invention are for a martensitic stainless hot rolled steel sheet having superior crack resistance, manufactured by a twin roll strip casting process, and a method for manufacturing the same, wherein the martensitic stainless hot rolled steel sheet comprises, by weight%, C:0.1 to 1.5%, Cr:12 to 15%, Ni:1% or lower, Ti:0.005 to 0.1%, and the balance Fe and unavoidably added impurities, and wherein a primary chrome carbide precipitated at a grain boundary is fragmented and refined. The key technical features of the present invention are also for a high hardness martensitic stainless cold rolled steel sheet manufactured by annealing and cold rolling the hot rolled steel sheet, and a method for manufacturing the same. According to the present invention, a twin roll strip casting process is applied, and grain boundary strengthening elements are added to prevent center segregation, crack and strip breakage during casting, thereby ensuring the stability of the casting process. In addition, a refined and uniform structure is formed in a steel, and high hardness knives or tools having edges with high quality can be manufactured from the steel.