利用TEC方法定量分析连铸保护渣结晶比

采用HF-200渣膜热流模拟仪获取了两种不同Li_2O含量的高铝钢连铸保护渣的固态渣膜和水淬渣,通过研磨、过筛和压样得到满足热膨胀仪实验尺寸的样品.利用热膨胀曲线(thermal expansion curve,TEC)法测定保护渣结晶比及其重现性,并通过DSC方法进行验证.结果表明:TEC方法能够测定保护渣的结晶比,其结果的重现性较好,相差最大2.7%,并且TEC测定结果与DSC测定结果相吻合;TEC开始收缩温度点和DSC玻璃化转变温度点一致,比DSC出现峰值的温度点要低;相比DSC法,TEC方法不会因为基线而产生积分误差,是一种研究保护渣结晶性能较好的方法.

Crystallization Fraction of Continuous Casting Mold Fluxes Using TEC Method

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.