Microstructure evolution and crystallography of directionally solidified Al2O3/Y3Al5O12 eutectic ceramics prepared by the modified Bridgman method  

作　　者：Xu Wang Nan Zhang Yujie Zhong BailingJiang Langhong Lou Jian Zhang Jingyang Wang 

机构地区：[1]Shool of Material Science and Engineering,Xi'an University of Technology,Xi'an,710048,China [2]School of Materials Science and Engineering,Xi'an Shiyou University,Xi'an,710065,China [3]Institute of Metal Research. Chinese Academy of Sciences,Shenyang,110016,China

出　　处：《Journal of Materials Science & Technology》2019年第9期1982-1988,共7页材料科学技术（英文版）

基　　金：financially supported by the National Natural Science Foundation of China (Nos. 51804252 and 51701156);the Equipment Pre-Research Foundation of China (Nos. 6140759040102 and 6140923040203);the Doctoral Starting Fund of Xi’an University of Technology (No. 101-451116013)

摘　　要：Large size,high-density(99.97%)and well-organized Al2O3/Y3Al5O12(YAG)eutectic ceramics were prepared by the modified Bridgman method.The evolution of the three dimensional microstructure and micropores were investigated.The diameter of the micro-pores and the porosity decreased during directional solidification.The average equivalent diam eter of the micro-pores was 2.41μm in the well-prepared eutectic ceramics.Most of the pores(98.07%)were smaller than 4μm.These data are comparable to those prepared by the optical floating zone method.The as-grown eutectic ceramics were polycrystalline,but the interfaces were well-bonded and there were no amorphous phases in the microstructure.The misfits of the different crystallographic relationships were calculated,and the bottleneck of the single-crystal preparation was identified.These results could provide theoretical guidance for the preparation of large,single-crystal Al2O3/YAG eutectic ceramics by the modified Bridgman method.Large size, high-density（99.97%） and well-organized Al2 O3/Y3 Al5 O12（YAG） eutectic ceramics were prepared by the modified Bridgman method. The evolution of the three dimensional microstructure and micropores were investigated. The diameter of the micro-pores and the porosity decreased during directional solidification. The average equivalent diameter of the micro-pores was 2.41 μm in the well-prepared eutectic ceramics. Most of the pores（98.07%） were smaller than 4 μm. These data are comparable to those prepared by the optical floating zone method. The as-grown eutectic ceramics were polycrystalline, but the interfaces were well-bonded and there were no amorphous phases in the microstructure. The misfits of the different crystallographic relationships were calculated, and the bottleneck of the single-crystal preparation was identified. These results could provide theoretical guidance for the preparation of large, single-crystal Al2O3/YAG eutectic ceramics by the modified Bridgman method.

关 键 词：Al2O3/YAG EUTECTIC ceramics CRYSTALLOGRAPHY Interfaces BRIDGMAN method 

分 类 号：TG[金属学及工艺]