| 摘要 |
PROBLEM TO BE SOLVED: To provide mold powder which exhibits excellent heat insulating effect while preventing the contamination of a molten steel, and to provide a continuous casting method using the mold powder. SOLUTION: (1) In the mold powder for continuously casting a steel, CaO/SiO<SB>2</SB>is 1.0 to 1.9, the content of Al<SB>2</SB>O<SB>3</SB>is 2 to 18%, the total content of Na<SB>2</SB>O, Li<SB>2</SB>O and F is 2 to 25%, the content of carbonate expressed in terms of carbon is 0.8 to 3.5%, the content of sodium nitrate is 1 to 5%, the content of carbon is 0.1 to 10%, the content of a Ca-Si alloy and/or metal Si is 2 to 10%, the content of iron oxide expressed in terms of Fe<SB>2</SB>O<SB>3</SB>is <2%, the content of Mn oxide expressed in terms of MnO is <3%, solidifying temperature is 1,050 to 1,250°C, and viscosity at 1,300°C is 0.04 to 0.8 Pa s. Preferably, the powder has a powdery grain form, and does not comprise both of alkali metal fluoride and cryolite. (2) In the continuous casting method for a steel, using the mold powder in the (1), a lead free-cutting steel or an extrafine carbon steel is cast. COPYRIGHT: (C)2007,JPO&INPIT
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