Abstract: Disclosed are austenitic stainless steel that can exhibit high strength while having non-magnetic properties, and a manufacturing method thereof. The high strength non-magnetic austenitic stainless steel according to an embodiment of present disclosure includes, in percent (%) by weight of the entire composition, C: 0.02 to 0.12%, Si: 1.2% or less, Mn: 0.5 to 2.0%, Cr: 17.0 to 22.0%, Ni: 11.0 to 15.0%, Mo: 3.0% or less, N: 0.25% or less, the remainder of iron (Fe) and other inevitable impurities, satisfies C+N: 0.25% or more, and satisfies following Formulas (1) and (2). [{Cr+Mo+1.5*Si+18}/{Ni+30*(C+N)+0.5*Mn+36}+0.262]*161?161?log(cooling rate)<0??(1) 551?462*(C+N)?9.2*Si?8.1*Mn?13.7*Cr?29*Ni?18.

Abstract: There is provided a method of manufacturing a high nitrogen duplex stainless steel sheet through a twin roll strip casting process without the occurrence of surface swelling on the high nitrogen duplex stainless steel sheet.

Abstract: There is provided a method for manufacturing a duplex stainless steel sheet having reduced inclusions through argon oxygen decarburization (AOD), ladle treatment (LT), and twin roll strip casting. The method includes deoxidizing molten steel using silicon (Si) during the AOD, wherein the molten steel has a silicon (Si) content of 0.55 wt % to 0.75 wt % at the end of the AOD.

Abstract: A stainless steel sheet for cookware and a method of manufacturing the same and, particularly, an induction heatable stainless steel sheet having excellent corrosion resistance and a method of manufacturing the same are provided. The induction heatable stainless steel sheet having excellent corrosion resistance includes, by wt %, C: 0.1% or less (excepting 0%), Si: 0.2% to 3.0%, Mn: 1.0% to 4.0%, Cr: 19.0% to 23.0%, Ni: 0.3% to 2.5%, N: 0.18% to 0.3%, Cu: 0.3% to 2.5%, iron (Fe) as a residual component thereof, and other unavoidable impurities, and has relative permeability of 20?r to 80?r. In addition, a microstructure includes, by volume %, ferrite: 30% to 70% and austenite as a remainder thereof.

Abstract: A method of manufacturing a martensitic stainless steel sheet by allowing ingot steel to pass through two casting rolls rotating in opposing directions through a twin roll strip caster is provided. The method includes rolling a steel sheet cast between the casting rolls at a temperature of 1000 to 1200° C. and a draft percentage of 25 to 50% with a first roller, and rolling the steel sheet at a temperature of 800 to 1000° C. and a draft percentage of 5 to 15% with a second roller.

Abstract: A surface treatment method capable of preventing a surface defect by improving a surface shape determining surface roughness of a casting roll and a casting roll manufactured by the surface treatment method, are provided. A surface treatment method includes a concave-convex pattern forming operation of forming a concave-convex pattern on a surface of a casting roll; and an electrolytic polishing operation of electrolytically polishing so that a plurality of convex portions and concave portions of a concave-convex pattern formed in the concave-convex pattern forming operation are treated to be rounded.

Abstract: There is provided a method of manufacturing a high nitrogen duplex stainless steel sheet through a twin roll strip casting process without the occurrence of surface swelling on the high nitrogen duplex stainless steel sheet.

Abstract: There is provided a method for manufacturing a duplex stainless steel sheet having reduced inclusions through argon oxygen decarburization (AOD), ladle treatment (LT), and twin roll strip casting. The method includes deoxidizing molten steel using silicon (Si) during the AOD, wherein the molten steel has a silicon (Si) content of 0.55 wt % to 0.75 wt % at the end of the AOD.

Abstract: The apparatus for preventing damage to casting rolls includes: a roll pressing force detection unit measuring a roll pressing force applied to the casting rolls; a foreign object determination unit determining whether foreign objects have been introduced to the casting rolls based on the measured roll pressing force; a roll gap instruction value generation unit generating a roll gap instruction value by adding a preset roll gap amount to the set roll gap if it is determined that foreign objects have been introduced to the casting rolls; and a roll gap control unit controlling a roll gap between the casting rolls based on the roll gap instruction value. Therefore, surfaces of the casting rolls may be less damaged by foreign objects.

Abstract: The apparatus for preventing damage to casting rolls includes: a roll pressing force detection unit measuring a roll pressing force applied to the casting rolls; a foreign object determination unit determining whether foreign objects have been introduced to the casting rolls based on the measured roll pressing force; a roll gap instruction value generation unit generating a roll gap instruction value by adding a preset roll gap amount to the set roll gap if it is determined that foreign objects have been introduced to the casting rolls; and a roll gap control unit controlling a roll gap between the casting rolls based on the roll gap instruction value. Therefore, surfaces of the casting rolls may be less damaged by foreign objects.

Abstract: A method of manufacturing a martensitic stainless steel sheet by allowing ingot steel to pass through two casting rolls rotating in opposing directions through a twin roll strip caster is provided. The method includes rolling a steel sheet cast between the casting rolls at a temperature of 1000 to 1200° C. and a draft percentage of 25 to 50% with a first roller, and rolling the steel sheet at a temperature of 800 to 1000° C. and a draft percentage of 5 to 15% with a second roller.

Abstract: Disclosed is a method of forming a continuous channel for gas discharge in the surface of a casting roll for twin roll strip casting, and particularly, a method of forming a continuous channel for gas discharge on the surface of a casting roll for twin roll strip casting, suitable for the formation of dimples on the surface of a casting roll for a twin roll strip caster, which includes applying a photoresist on the entire surface of a casting roll, conducting patterning on the applied photoresist, developing the surface of the casting roll, subjected to the patterning, and etching the metal surface of the casting roll, exposed in the developing, and which prevents the generation of dents, enables the manufacture of a cast product having no defects, and realizes wide applicability not only to high Mn steel but also to types of casting steel capable of generating dents or similar defects due to a large amount of volatile gas.

Abstract: Disclosed is a method of forming a continuous channel for gas discharge in the surface of a casting roll for twin roll strip casting, and particularly, a method of forming a continuous channel for gas discharge on the surface of a casting roll for twin roll strip casting, suitable for the formation of dimples on the surface of a casting roll for a twin roll strip caster, which includes applying a photoresist on the entire surface of a casting roll, conducting patterning on the applied photoresist, developing the surface of the casting roll, subjected to the patterning, and etching the metal surface of the casting roll, exposed in the developing, and which prevents the generation of dents, enables the manufacture of a cast product having no defects, and realizes wide applicability not only to high Mn steel but also to types of casting steel capable of generating dents or similar defects due to a large amount of volatile as.

Abstract: Disclosed is a casting roll for a twin roll strip caster, and particularly, a casting roll for a twin roll strip caster, in which a continuous gas channel, for preventing the generation of dents in the surface of a strip when casting TWIP steel in order to improve the mechanical properties of the strip, including increasing the tensile strength and elongation, is formed in the surface of the casting roll, thus discharging gas mixed when the strip is cast, thereby preventing the generation of dents in the surface of the strip when casting the TWIP steel, in particular, a continuous gas channel is formed, thereby decreasing a conventional dent index and discouraging the generation of dents.