| It has built the mathematical model for heat transfer during solidification of steel in the mould of H-type steel caster. The finite element software, ANSYS, has been applied to simulate solidification process. And analyzed the behavior of steel heat transfer and solidification in beam blank continuous casting. Proved up the rule and influencing factors on the temperature distribution of slab and the growth history of solidification shell. According to the solidification characteristics and the metallurgical properties in the mold of different kinds steel, the performance of mold flux has been analyzed. Put forward the performance which suitable for production, such as the melting temperature, viscosity. Then proceed from the physical and chemical characteristics, combined with experiment research and theoretical analysis, take the component design optimization for mold flux of beam blank continuous casting.First, the performance of current mould flux used in Jin Xi H-type continuous casting is researched. Then experimental research and theoretical analysis about chemical components, melting temperature, melting speed, and viscosity of mold flux are carried through. Finally, it has found that the melting was 1167℃, the melting speed was 57s and the viscosity was 0.77Pa?s. It can't satisfy the requirement of beam blanks casting.Mathematical model of heat transfer for slab is established in this paper according to ANSYS, on the basis of which analog simulation of solidifying process for slab is carried through. The temperature distribution and growth history of solidifying shell have been described successfully. The influences of different processing parameters on mould heat transfer are also researched, which provide a theoretical basis for setting down rational processing parameters, optimizing the mold flux performance, improving slab quality and reducing slab cracks.Designed the orthogonal experiment scheme, the experiment of mold flux has researched. And measured the melting temperature of mold flux with sample's deformation method, confirmed the viscosity with empirical formula, confirmed the melting speed with optimal distribute carbon method. Finally, analyzed the influence of each chemistry composition upon the physical and chemical characteristics of flux. According to the solidification characteristic of Q235B steel, and combining the characteristics of many cross-section on beam blanks continuous casting, confirmed the melting temperature was less than 1096℃, the melting speed was 30~40s and the viscosity was 0.17~0.4Pa?s that is suitable for this steel, in the condition of the casting speed is 1.2m/min and the wide side mould cooling water is 176t/h. Finally, combining the experimental results, the best choice is the 14# mold flux which R(alkalinity) is 1.0, the melting temperature is 1092℃, the melting speed is 32.5s and the viscosity is 0.27Pa?s. Through initial application prove, it can satisfy the requirement of H-type Q235B steel casting.
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