Aoki Yuta, Masuda Hiroshi, Tochigi Eita, Yoshida Hidehiro
Department of Materials Science and Engineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan.
Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo, 153-8505, Japan.
Nat Commun. 2024 Oct 16;15(1):8700. doi: 10.1038/s41467-024-53026-6.
High-strength ceramic materials are known for their exceptional mechanical properties; however, they are often plagued by brittleness, limiting their applications. Because of the inherent difficulty of dislocation glide and multiplication in ceramics, efforts to overcome the brittleness of ceramics by activating plastic deformation have faced challenges. This work demonstrates that AlO-GdAlO (Gadolinium Aluminum Perovskite: GAP) eutectic micropillars with submicron-scale fibrous microstructures exhibit remarkable plastic deformability. They displayed engineering plastic strains of up to 5% even at 25 °C, while the micropillars of AlO or GAP single crystals exhibited brittle fracture similar to conventional high-strength ceramics. The plasticity in AlO-GAP eutectic was attributed to the activation of primary prismatic slip and secondary basal slip in the AlO phase, which is typically considered inactive at room temperature. These findings suggest that plastic deformability can be achieved in high-strength ceramic materials by fabricating refined eutectic microstructures.
高强度陶瓷材料以其优异的力学性能而闻名；然而，它们常常受到脆性的困扰，限制了其应用。由于陶瓷中位错滑移和增殖的固有困难，通过激活塑性变形来克服陶瓷脆性的努力面临挑战。这项工作表明，具有亚微米级纤维微观结构的AlO-GdAlO（钆铝钙钛矿：GAP）共晶微柱表现出显著的塑性变形能力。即使在25°C时，它们也能展现出高达5%的工程塑性应变，而AlO或GAP单晶微柱则表现出类似于传统高强度陶瓷的脆性断裂。AlO-GAP共晶中的塑性归因于AlO相中一次棱柱滑移和二次基面滑移的激活，而AlO相通常被认为在室温下是不活跃的。这些发现表明，通过制造精细的共晶微观结构，可以在高强度陶瓷材料中实现塑性变形能力。
