30-03-2017 дата публикации
Номер: US20170087624A1
Принадлежит:
A mold flux is used in continuous casting of Ti-containing hypo-peritectic steel so as to prevent longitudinal cracks from forming on a surface of a slab. The mold flux contains CaO, SiO, an alkali metal oxide and a fluorine compound as major components. f(1), f(2) and f(3), which are calculated from the initial chemical composition, are (1.1−0.5×T) to (1.9−0.5×T), 0.05 to 0.40 and 0 to 0.40, respectively, if the Ti content of the molten steel (mass %) is T. The TiOcontent in the melting state during the casting is no more than 20 mass % and the ratio of the first peak height of perovskite to the first peak height of cuspidine in the mold flux film is no more than 1.0. 1{'sub': '2', 'the mold flux contains CaO, SiO, an alkali metal oxide and a fluorine compound as major components,'}chemical composition of the mold flux before the mold flux is put into a mold satisfies the formulas (1), (2) and (3),{'sub': '2', 'a TiOcontent of the mold flux in a melting state during the casting is no more than 20 mass %, and'} [{'br': None, 'i': ×T≦f', '×T, '1.1−0.5(1)≦1.9−0.5\u2003\u2003(1)'}, {'br': None, '0.05≦f(2)≦0.40 \u2003\u2003(2)'}, {'br': None, '0≦f(3)≦0.40 \u2003\u2003(3),'}, {'br': None, 'wherein in the formulas (1) to 3),'}, {'br': None, 'i': 'f', 'sub': h', '2', 'n, '(1=CaO)/(SiO)\u2003\u2003(A)'}, {'br': None, 'i': 'f', 'sub': 2', 'h', 'h', '2', 'h', '2', 'h, '(2)=(CaF)/{(CaO)+(SiO)+(CaF)}\u2003\u2003(B)'}, {'br': None, 'i': 'f', 'sub': h', 'h', '2', 'h', 'h, '(3)={(alkali metal fluoride)}/{(CaO)+(SiO)+(alkali metal fluoride))}\u2003\u2003(C)'}, {'br': None, 'wherein in the formulas (A) to (C),'}, {'br': None, 'sub': h', 'CaO', '2', 'h, '(CaO)=W−(CaF)×0.718 \u2003\u2003(D)'}, {'br': None, 'sub': 2', 'h', 'SiO2, '(SiO)=W\u2003\u2003(E)'}, {'br': None, 'sub': 2', 'h', 'F', 'Li2O', 'Na2O', 'K2O, '(CaF)=(W−W×1.237−W×0.613−W×0.406)×2.05 \u2003\u2003(F)'}, {'br': None, 'sub': h', 'Li2O', 'Na2O', 'K2O, '(alkali metal fluoride)=W×1.74+W×1.35+W×1.23 \u2003\u2003(G)'}], 'a ...
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