【作者】 雷作胜； 金小礼； 任忠鸣； 邓康； 钟云波；

【Author】 LEI Zuosheng JIN Xiaoli REN Zhongming DENG Kang ZHONG Yunbo (Shanghai University,Shanghai Key Laboratory of Modern Metallurgy & Material Processing,China)

【机构】 上海大学上海市现代冶金与材料制备重点实验室；

【摘要】 通过独特设计的实验测量了结晶器振动过程中,连铸初始凝固点温度变化情况,发现初始凝固点温度存在与结晶器振动相对应的温度波动现象。传热数学解析表明,在结晶器内侧存在温度波动的情况下,无论有无保护渣,在钢水内部每一点都存在着与表面温度波动频率一致的温度波动,但其幅值随深度的增加而下降；在无保护渣的情况下,表面温度波动在钢水中的渗透深度约为1~2mm；保护渣的存在对温度波动有很大的衰减作用,因而能提高铸坯表面的质量；另外,采用高频率小振幅的振动,降低保护渣导热率,增加保护渣道宽度,都能有效地减小温度波动对初始凝固坯壳的影响。这一现象可以用来解释现有的一些技术改善铸坯表面质量的原因。更多还原

【Abstract】 The Initial Solidified Point(ISP)temperature fluctuation during continuous casting caused by mold reciprocation was measured by a newly developed method.The repeated experiments results show that the ISP temperature varied periodically along with mold oscillation.A one-dimension heat transfer mathematic model shows that when there was a temperature fluctuation in the inner mould wall,there were corresponding temperature fluctuations at every point in the molten steel,whose frequency is the same as the boundary condition and amplitude decreased along with the increasing depth whether there was mould flux between mould and steel or not.The influence depth of surface temperature fluctuation in molten steel is about 1～2 mm when there was no mould flux.The surface temperature fluctuation attenuated rapidly when there was mould flux.Therefore mould flux was helpful to improve the billets surface quality.In addition,high frequency and low amplitude mould oscillation,decrease the thermal conductivity of mould flux and increase the mould flux channel width are all helpful to decrease the influence on early solidified shell caused by surface temperature fluctuation.Based on the phenomenon,the mechanism of how some technologies improve surface quality of continuous casting billets is analyzed. Their common mechanism was the decreasing of the temperature fluctuation of early solidification shell.更多还原