Analysis of lubrication and heat transfer function of mold flux
HE Yu-ming1, HE Sheng-ping2
1. Steelmaking Plant, Chongqing Iron and Steel Co., Ltd., Chongqing 401258, China; 2. College of Materials Science and Engineering, Chongqing University, Chongqing 400044, China
Abstract:Functions of mold flux film in lubrication and heat transfer control are analyzed. The physical properties of mold flux film, such as viscosity temperature curve, transition temperature, crystalline state and precipitated phase are studied. It is pointed out that the transition temperature and crystalline rate of mold flux film play a major role in lubrication. The closed pore ratio, surface roughness and cuspidate ratio of the slag film have key effects on heat transfer control. At the same time,the solidification characteristics of slag film of three typical mold fluxes were studied. The basic property parameters of the mold fluxes suitable to the characteristics of steel grades and continuous casting process, such as basicity, melting point, viscosity, turning point temperature, sintering performance and gas in slag film and so on lubrication and heat transfer control were discussed. The key control contents of mold flux management are put forward, such as the total water content of mold flux, the continuous influence of replacing different performance mold flux on heat transfer and lubrication, and the reasonable depth of liquid slag pool.
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