Can orientations of directionally solidified dual-phase Al_(2)O_(3)/YAG eutectics be induced by single-phase sapphire seeds?  

作　　者：Liangting He Xu Wang Jiaze Li Wangshuai Xiang Fuxue Yan Bailing Jiang Qiaodan Hu 

机构地区：[1]School of Materials Science and Engineering,Xi’an University of Technology,5 South Jinhua Road,Xi’an 710048,China [2]Center for Advanced Structural Materials,Department of Mechanical Engineering,City University of Hong Kong,Hong Kong 999077,China [3]School of Materials Science and Engineering,Shanghai Jiao Tong University,Shanghai 200240,China

出　　处：《Journal of Materials Science & Technology》2023年第11期216-224,共9页材料科学技术（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(Nos.52171046,51804252,52234010,and 51922068).

摘　　要：Directionally solidified dual-phase Al_(2)O_(3)/Y_(3)Al_(5)O_(12)(YAG)eutectic ceramics(DSECs)typically exhibit strong anisotropy.To improve their properties,various single-phase sapphire seeds,including r-axis[1-102],m-axis[10-10],c-axis[0001],and a-axis[11-20],were used as seeds to induce the orientation of the Al_(2)O_(3)/YAG DSECs.The results showed that Al_(2)O_(3) in the eutectics could be governed by the sapphire seeds.The YAG in each induced eutectic had a specific growth direction endowed by Al_(2)O_(3) in the asinduced eutectics or the sapphire seed.Herein,we calculated the planar lattice misfits and interfacial strain energies of four crystallographic orientation relationships based on the constructed lattice models.It was elucidated the constraint of the sapphire seed caused YAG to grow following the rule of mini-mizing the interfacial strain energy.This revealed the reason why Al_(2)O_(3)/YAG DSECs orientation can be successfully induced.These results may provide a novel method for the design of high-performance eu-tectic ceramic materials.

关 键 词：Al_(2)O_(3)/Y_(3)Al_(5)O_(12) Directional solidification Single-phase sapphire seed Crystallographic orientation relationship Interfacial strain energy 

分 类 号：TG244.3[金属学及工艺—铸造] TG141[一般工业技术—材料科学与工程]