Fabrication of Ceramics Nano-Composites by Casting of Eutectic Melts in Multi-Component Systems

（1）采用Al_2O_3-HfO_2-GdAlO_3三元系共晶熔体熔铸法制备透明块体陶瓷，并通过适当的热处理制备三元纳米复相陶瓷（论文1、3）。(2)从三元系Al_2O_3-CaO-Y_2 O_3中的伪二元C_ A_7-CoYAlO_4系共晶熔体制备透明块体材料<12>，并通过适当的退火制备二元纳米复合材料（论文2，4，11）。（3）计算机模拟可以描述这些体系中熔体的凝固过程，从而解释它们的纳米/介观/微观结构（论文5-8）。（4）这些非晶基质和/或三元化合物CaLaGaO_4可以通过掺杂Eu形成红色荧光体（论文3，9&amp;10）。[II]它们的重要性陶瓷纳米复合材料通常是由混合粉末通过固态工艺制备的：（1）通过固态反应合成它们，（2）粉末的分散，（3）粉末的成型，（4）烧结。而本研究采用的方法是：（1）制备均匀的共晶熔体，（2）在具有所需形状的模具中浇铸，制备非晶块体，（3）退火，制备纳米结构材料。因此，该方法不仅可以制备出粉末烧结难以制备的透明纳米复合材料，而且可以制备出成分均匀的多组分固溶体样品。因此，本方法使用共晶熔体的熔融/浇铸，可以评价为纳米复合陶瓷的创新方法。它被授予最佳海报奖（论文#3）和国际期刊封面（论文#1）。

[I]Major Establishments(1)The preparation of transparent bulk ceramics by melting/casting of eutectic melt in the ternary system Al_2O_3-HfO_2-GdAlO_3, and fabrication of ternary nano-composite ceramics by appropriate annealing of them (Papers 1 & 3).(2) The preparation of transparent bulk materials from the eutectic melt in pseudo-binary C_<12>A_7-CoYAlO_4 system in the ternary system Al_2O_3-CaO-Y_2O_3, and the fabrication of binary nano-composites by appropriate annealing of them (Papers 2,4 & 11).(3)The computer simulation can depict the solidification of the melts in these systems, thus explains their Nano-/Meso-/Micro-structures (Papers 5-8).(4)Those amorphous matrices and/or the ternary compound CaLaGaO_4 can be formed as a red phosphor by doping Eu (Papers 3,9 & 10).[II]Their ImportanceCeramics nano-composites have generally been fabricated from mixed powders by solid state processes : (1) Synthesis of them by solid state reactions, (2) the dispersion of powders, (3) molding of powders, (4) firing for sintering. Those processes are difficult to prepare homogeneous products and nano-structure controlled ones, because higher temperature firing would bring about the grain growth of every phase.The present research, on the other hand, (1) makes the homogeneous eutectic melts, (2) casts in a mold with the desired shape to fabricate the amorphous bulk, then (3) anneals to result in the nano-structures materials. Therefore, transparent nano-structured composites, which were very difficult to fabricate from powders by sintering, can be produced.Moreover, the solid solution samples with multi-components with homogeneous compositions can be produced by this method easily. The present method using melt/cast of eutectic melts, therefore, could be evaluated an innovative method for nano-composites ceramics. It was awarded as one of the best poster award (Paper #3) and the cover page of an International Journal (Paper #1).