东北大学毕业设计（论文） 摘要材料成型与控制工程毕业论文镁合金铸轧区温度场仿真及组织研究单 位 名 称：材料与冶金学院专 业 名 称：材料成型与控制工程镁合金铸轧区温度场仿真及组织研究镁合金是最轻的金属结构材料，其比强度和比刚度高，阻尼性及机加工性好，具有防震、屏蔽电磁波等优异性能，近年来得到极大重视，在国防、航空航天以及3C、汽车等民用工业部门得到了广泛地应用。镁合金的双辊薄带连续铸轧技术是当今有色行业主要研究的课题之一，具有短流程、低能耗及节省投资等优点。应用模拟软件，进行镁合金双辊薄带连续铸轧过程的数值模拟，寻求最佳工艺参数，为镁合金的连续铸轧提供理论基础。本文通过大型模拟软件ANSYS研究了不同的浇注温度、不同的铸轧速度以及不同的辊带间对流换热系数对铸轧区内镁熔体温度场和流场的影响；通过轧卡实验得到一定条件下的铸轧区凝固样品，并观察其凝固组织；论文得到了如下结果：（1）随着浇注温度的升高，铸轧区内的整体流动趋势差别不大，各处温度均有所升高，液穴长度增大，液固两相区增大，轧辊咬入端附近两相区凝固壳变薄，凝固终点位置靠近轧制出口端，出口板带温度也升高。（2）随着铸轧速度的提高，铸轧区内的液穴长度增大，液固两相区增大，铸带表面温度升高，凝固壳变薄，凝固终点位置向轧制出口端靠近。铸轧区中部的两个漩涡略向轧制出口端偏移。（3）随着辊带间对流换热系数的增大，铸轧区内的液穴的长度减小，液固两相区变小，凝固壳略变厚，凝固终点位置向咬入端偏移。铸轧区中部的两个漩涡也向咬入端偏移。（4）铸轧区的凝固组织，靠近轧辊边部的晶粒比中间部位的细小且等轴化程度更高；边部的晶粒则是越靠近轧制出口端越细小。关键词：数值模拟，镁合金，铸轧，温度场，流场 东北大学毕业设计（论文） AbstractNumerical Simulation on Temperature Field and the Study on Microstructure of Cast-rolling Zone of Magnesium AlloyMagnesium alloys are the lightest constructional metal materials. Due to their excellent properties such as high specific strength and stiffness, good damping and machinability, shock resistance, electromagnetic shielding, magnesium alloys are deemed as one of the most potential materials, and have received more and more attention. Magnesium alloys are rapidly applied to national defence, aeroplane, 3C, automobile and so on. The technique of twin-roll strip continuous cast-rolling of magnesium alloys is one of the main research tasks in nonferrous industry now, it possesses the advantages such as short procedure, low energy consumption, less investment. Simulative software can simulate the process of twin-roll strip continuous cast-rolling of magnesium alloys to get the proper processing parameters, and provide theoretical basis for continuous cast-rolling of magnesium alloys.In this paper, the effect of point of pouring, cast-rolling speed and heat convection coefficient was studied on the temperature and flow field of magnesium melt in the cast-rolling zone by ANSYS; also solid sample was obtained by experiment to study the solid microstructure in the cast-rolling zone, and the conclusions were obtained as follow:（1）With the increment of point of pouring, the flow tendency in the cast-rolling zone is hardly changed, the temperature everywhere in the cast-rolling zone increases more or less, the length of the liquid cave increases, the semi-solid region enlarges, the semi-solid shell around the nip point thins, freezing point is near to outlet and the temperature of strip in outlet also increases.（2）With the increment of cast-rolling speed, the length of the liquid cave increases, the semi-solid region enlarges, the surface temperature of strip increases, the semi-solid shell thins, freezing point is near to outlet and the two eddies in the middle of the cast-rolling zone shift to outlet appreciably.（3）with the increment of heat convection coefficient, the length of the liquid cave reduces, the semi-solid region diminishes and the semi-solid shell thickens appreciably. The freezing point and the two eddies in the middle of the cast-rolling zone are near to the nip point.（4）For the solid microstructure of the cast-rolling zone, the grains around the rolls are finer and more equiaxial than those in the middle of the cast-rolling zone. For those grains around the rolls, the nearer they are to outlet , the finer they are. Key words: numerical simulation，magnesium alloy，cast-rolling，temperature field，flow field 东北大学毕业设计（论文） 目录目 录任务书i中文摘要iiABSTRACTiii第1章 绪论11.1 金属镁及其合金11.1.1 镁的基本性质及特点11.1.2镁合金的合金成分、牌号标记及其分类31.1.3镁合金的应用及国内外发展现状51.2 板带铸轧技术的提出与发展现状2071.2.1 国外简况71.2.2 国内简况