High Temperature Characteristics of Unidirectionally Solidified Al₂O₃/GAP Eutectic Composites with a Novel Microstructure

Abstract:

Much attention has been paid to unidirectionally solidified ceramic composites as candidates for high-temperature structural materials. We have recently developed potential ceramic eutectics, which are named Melt Growth Composites (MGC). The Al₂O₃/GAP(GdAlO₃) binary MGC has a novel microstructure, in which continuous networks of single-crystal Al₂O₃ phases and single-crystal GAP phases interpenetrate without grain boundaries. Chain structure in the Al₂O₃/GAP binary system is formed due to the frequent branching of both phases resulted in the entangled structure. Therefore, the Al₂O₃/GAP binary MGC has excellent high-temperature characteristics in the air atmosphere at very high temperatures. In the paper, high temperature strength, thermal stability of microstructure and strength, and fracture toughness of the Al₂O₃/GAP binary MGC are reported.

• Periodical: Materials Science Forum (Volumes 706-709)
• Pages: 246-251
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.706-709.246
• Online since: January 2012
• Authors: Yoshiharu Waku, Hideki Ohtsubo, Narihito Nakagawa, Hideyuki Yasuda
• Keywords: Eutectic Composite, Fracture Toughness, High Temperature Strength, Single Crystal, Thermal Stability, Unidirectional Solidification

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