Micro- and macro-modeling of solidification process

Nagashima等人提出了一种新的方法来测量熔融温度附近的扩散系数和粘度变化，这是用常规方法难以测量的。该方法利用了熔体中细颗粒的瑞利散射和布朗运动。对熔融KNO_3和NaNO_3也证明了这种可能性。数据表明，在熔融温度附近的最大和最小粘度增加之间的差异反映了液体结构的变化。Ohnaka等人阐明了具有与氧化物高温超导体相似相图的有机材料体系的生长机制，并建立了一个微观模型，可以模拟这种生长现象。此外，他们还提出了一种新的机制，颗粒吞没在固/液界面。Hayashi等人发展了一种考虑微观结构和凝固现象的动力学理论，用于研究过冷液体中非小面自由枝晶的生长， ...更多信息 在冷却壁附近的生长伴随着温度弛豫和固相粗化。该理论是基于他们对Bi-Sn合金凝固的实验工作。Tsukada的小组揭示了生长条件（炉结构和包括晶体中的热应力在内的传输现象）与晶体质量之间的关系，特别是通过CZ法生长氧化物单晶时的微裂纹。本工作建立在LiNbO_3单晶生长的数值模拟和实验观察的基础上。最后，Nakayama的小组已经能够定量地研究三维电路中所需的引线的小型化。他们发展了一种分析薄合金凝固过程的方法，并通过实验验证了这一方法的有效性，这些工作进一步阐明了微观和宏观模型及其结合对利用各种凝固过程改进新材料和器件的必要性，并发展了一些新的模型方法。少

Nagashima's groups has proposed a new method to measure diffusion coefficient and viscosity change near melting temperature, which is difficult to measure with conventional methods. This method uses Rayleigh scattering and Brownian motion of fine particles dispersed in melt. The possibility has been demonstrated for molten KNO_3 and NaNO_3. The data showed the difference between the maximum and minimum viscosity increases near the melting temperature reflecting liquid structure change. Ohnaka's group has made clear the growth mechanism of an organic materials-system which has the similar phase diagram of oxide high temperature superconductors, and developed a micro-model, which can simulate the growth phenomena. Further, they have proposed a new mechanism for particle engulfment at the solid/liquid interface. Hayashi's group has developed a kinetic theory considering microstructure and solidification phenomena for non-facetted free dendritic growth in undercooled liquid and also for th … More e growth near a cooled wall accompanying temperature relaxation and solid phase coarsening. The theory was based on their experimental work on the solidification of Bi-Sn alloy. Tsukada's group has revealed the relationship between growth condition (furnace structure and transport phenomena including thermal stress in crystals) and crystal quality especially micro-cracks for oxide single crystal growth by the CZ method. This work in based on numerical simulation and experimental observation of growth of LiNbO_3 single crystal. Finally, Nakayama's group has made it possible to investigate quantitatively the miniaturization of leads required in three dimensional electric circuits. Namely they developed a method to analyze the solidification process of elongating thin molten alloys and validated their method with experimental works.These works have made more clear the necessity of the micro- and macro-modeling and their combination to improve new materials and devices by using various solidification processes, and some new modeling methods have been developed. Less