基于熔池边界层温度的双辊铸轧界面换热数学模型  

Mathematic Model of Interfacial Heat Transfer for Twin-roll Strip Casting Based on Boundary Temperature of Molten Pool

作　　者：田敏[1,2] 许志强[1,2] 吕征[1,2] 杜凤山[1,2] 

机构地区：[1]燕山大学国家冷轧板带装备及工艺工程技术研究中心,河北秦皇岛066004 [2]燕山大学机械工程学院,河北秦皇岛066004

出　　处：《铸造技术》2016年第2期268-272,共5页Foundry Technology

基　　金：国家自然科学基金资助项目(51374184);河北省自然科学基金-钢铁联合研究基金资助项目(E2013203342)

摘　　要：熔池与结晶辊接触界面的换热边界条件是制定双辊薄带铸轧工艺的重要参数。针对现有的换热数学模型不能合理描述铸轧开浇和稳定阶段接触界面的热交换问题,基于熔池边界层温度和凝固组织枝晶间距建立了接触界面的换热数学模型。以1Cr18Ni9Ti不锈钢为例,对铸轧稳定阶段的数学模型进行了计算,模型计算结果与试验结果相吻合,验证了本文所建立换热数学模型的准确性。研究结果表明,钢液与结晶辊初始接触时界面热流密度为26.06 MW·m-2,随着接触界面熔池边界层温度降低,凝固坯壳收缩,热流密度显著下降,在接近Kiss点区域时趋于稳定值。Aimed at the case that the interracial heat exchange during initial pouring process and stabilization stage cannot be described reasonably by existing mathematic model of heat transfer, the mathematical model of interfacial heat flux was derived, which was calculated on the basis of the boundary temperature of molten pool and arm spacing of solidification structure. Taking 1Crl8Ni9Ti stainless steel as an example, the mathematical model was calculated and its veracity was certified, the calculated results were agreeable to the experimental ones. The results show that the heat flux density is 26.06 MW·m^-2 when liquid steel just contacting with the casting rolls. The solidified shell shrinks with the decrease of temperature, so the heat flux density reduces obviously and becomes a fixed value closing to the area of the Kiss point.

关 键 词：双辊薄带铸轧 界面换热数学模型 熔池边界层温度 二次枝晶间距 

分 类 号：TG335.9[金属学及工艺—金属压力加工]