高碳钢连铸保护渣的性能

为了研究高碳钢保护渣在连铸过程中的匹配性,对典型工业高碳钢保护渣的熔化、润湿、黏度、渣膜分布,以及传热性能进行研究。结果表明,4个高碳钢保护渣的开始熔化温度范围为1 110~1 129 ℃,润湿角范围为30.1°~37.8°,黏度范围为0.210~0.312 Pa·s,转折温度范围为1 046~1 130 ℃,渣膜的液态层比例为14.7%~18.9%。其中,1号高碳钢保护渣熔化温度较低(熔化区间1 110～1 345 ℃)、黏度较低(0.264 Pa·s)、渣膜液态层较高(比例为18.9%)、转折温度(1 059 ℃)和控热能力均适宜,表明该渣在高碳钢连铸结晶器中可以迅速熔化,形成足够的液态渣,并从弯月面渗入渣道,形成均匀的渣膜,从而润滑铸坯,避免黏结漏钢和裂纹等缺陷,保障高碳钢连铸的顺行。

Properties of mold fluxes for casting high carbon steel

In order to study the compatibility of mold fluxes for casting high carbon steel in the process of continuous casting, the melting, wettability, viscosity, phase distribution and heat transfer ability of typical mold fluxes for casting high carbon steel have been investigated. The results show that the ranges of the initial melting temperature, wetting angle, viscosity, breaking temperature and liquid layer ratio of the four mold fluxes are 1 110-1 129 ℃, 30.1°-37.8°, 0.210-0.312 Pa·s, 1 046-1 130 ℃ and 14.7%~18.9%, respectively. Among these mold fluxes, mold flux 1 can melt very fast to form liquid slag, and infiltrate the gap between mold wall and shell to form even slag film, since its melting temperature (1 110-1 345 ℃) and viscosity (0.264 Pa·s) are relatively low, liquid layer ratio (18.9%) is relatively high, and break temperature (1 059 ℃), as well as heat transfer ability are appropriate. These advantages can reduce the stick breakout and cracks, meanwhile smooth the high carbon steel continuous casting process.