Crystallization Fraction of Continuous Casting Mold Fluxes Using TEC Method

doi:10.12068/j.issn.1005-3026.2017.01.015

Abstract

Abstract: The solid slag film and quenched slag of a high-Al steels mold flux with different Li₂O contents were obtained by a HF-200 heat flux simulator. Through grounding， sieving and compacting， the size of the obtained specimen can meet the requirement of TEC (thermal expansion curve) measurement. The crystallization fraction and the reproducibility of data were investigated by the TEC method and proved by the DSC (differential scanning calorimeter) method. The results show that the TEC method can be employed to study the crystallization fraction of mold fluxes. The method is accurate， reliable and reproducible， with maximum difference of 2.7%. The results obtained by TEC agree well with DSC measurements. The temperature of starting to shrink on TEC curve is in accordance with the glass transition temperature on DSC curve， and is lower than the peak temperature of DSC curve. Compared with DSC method， the TEC method does not lead to uncertainty in the determination of the area due to the baseline shift in DSC， and is thus a better method to study the crystallization of mold fluxes.

Key words: continuous casting, mold fluxes, crystallization fraction, TEC (thermal expansion curve), DSC (differential scanning calorimeter)

CLC Number:

TF03⁺1

YU Liang， WEN Guang-hua， TANG Ping， YANG Chang-lin. Crystallization Fraction of Continuous Casting Mold Fluxes Using TEC Method[J]. Journal of Northeastern University Natural Science, 2017, 38(1): 71-75.

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