Effect of seed orientations on crystallographic texture control in faceted Al2O3/YAG eutectic ceramic during directional solidification  

作　　者：Yuan Liu Haijun Su Zhonglin Shen Di Zhao Yinuo Guo Shanding Li Min Guo Lin Liu Hengzhi Fu 

机构地区：[1]State Key Laboratory of Solidification Processing,Northwestern Polytechnical University,Xi’an 710072,China [2]Research&Development Institute of Northwestern Polytechnical University in Shenzhen,Shenzhen 518057,China

出　　处：《Journal of Materials Science & Technology》2023年第15期86-101,共16页材料科学技术（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.52130204,52174376 and 51822405);the Guangdong Basic and Applied Basic Research Foundation(No.21201910250000848);the Science and Technology Innovation Team Plan of Shaan Xi Province(No.2021TD-17);the Joint Research Funds of the Department of Science&Technology of Shaanxi Province and NPU(No.2020GXLH-Z-024);The Youth Innovation Team of Shaanxi Universities,the Key R&D Program of Shaanxi Province(No.2019ZDLGY 04-04);the Fundamental Research Funds for the Central Universities(No.D5000210902);the Innovation Foundation for Doctor Dissertation of Northwestern Polytechnical University(Nos.CX2021056,CX2021066 and CX2022033),China.

摘　　要：Crystallographic texture control is a major challenge in directionally solidified multiphase eutectic ceramics with complex faceted growth characteristics.In this study,the Czochralski(CZ)technique is proposed to prepare eutectic single crystal ceramic with large size(30 mm×125 mm).A highly oriented and unique texture of Al_(2)O_(3)/Y_(3)Al_(5)O_(12)(YAG)eutectic ceramic is formed via the 112¯0Al_(2)O_(3) single crystal seed induction based on crystallographic orientation tailoring.The orientations of Al_(2)O_(3)/YAG eutectic are more strictly constrained by single crystal seed induction on the basis of the minimum interface energy principle,resulting in a defined single orientation relationship along the solidification direction.In particular,the single crystallographic orientation can be obtained in a short competitive solidification distance under the influence of epitaxial solidification from single crystal seed.Therefore,it has been confirmed that the orientations of 112¯0Al_(2)O_(3) and 111YAG are preferentially stabilized with the minimum under-cooling during directional solidification.Crystallographic orientation disturbances and instabilities due to polycrystalline crystal seed are avoided.Finally,the successful texture control inducted by 112¯0Al_(2)O_(3) single crystal seed can provide a promising orientation design pathway for faced oxide eutectic solidification.

关 键 词：Seeding method Directional solidification Al_(2)O_(3)/YAG eutectic single crystal ceramic Crystallographic orientation 

分 类 号：TQ174.1[化学工程—陶瓷工业]