| 摘要 |
<p>1. Finely-divided slagging agent for the continuous casting of steel which tends to release aluminium oxide into the slagging agent during its use in the molten state, characterised in that it has a fluidity of about 10.2 to 40.6 cm (4 to 16 inches), a melting range which, at most, is not substantially above 1,260 degrees C (2,300 degrees F) and a start-up ADK value of not more than 500 seconds, and is further characterised by the following theoretical net oxide analysis values in the ranges mentioned below, the percentages being understood as percentages by weight and being chosen so that the sum is 100% : Constituents of the fluxing agent (*) % by weight (**) CaO* (*) 0-42 (**) MgO* (*) 0-20 (**) BaO* (*) 0-20 (**) SrO* (*) 0-20 (**) MnO* (*) 0-20 (**) FeO* (*) 0-18 (**) F* (*) 4-16 (**) B2 O3 * (*) 0-15 (**) Na2 O (*) 1-25 (**) K2 O (*) 0-5 (**) Li2 O (*) 0-5 (**) V2 O5 (*) 0-1 (**) NiO (*) 0-2 (**) CuO (*) 0-2 (**) ZnO (*) 0-1 (**) TiO2 (*) 0-5 (**) ZrO2 (*) 0-3 (**) CoO (*) 0-2 (**) Cr2 O3 (*) 0-2 (**) MoO3 (*) 0-1 (**) Glass network former (*) SiO2 (*) 20-40 (**) Al2 O3 (*) 0-12 (**) P2 O5 (*) 0-10 (**) B2 O3 (*) included above (**) and the ratio of the sum of the theoretical net oxide analysis values of the fluxing-agent constituents marked with an asterisk to the theoretical net oxide analysis value of SiO2 (this ratio is designated as the R' ratio) is fixed beforehand at 1.5:1 to 3:1 in order to reach an operational ADK value which is not substantially above 750 seconds at most.</p> |
