Mechanical properties of directionally solidified Al2O3/Y3Al5O12 eutectic ceramic prepared by optical floating zone technique. Issue 10 (August 2018)

• Record Type: Journal Article
• Authors: Wang, Xu; Tian, Zhilin; Zhang, Wen; Zhong, Yujie; Xian, Quangang; Zhang, Jian; Wang, Jingyang
• Is Part Of: Journal of the European Ceramic Society. Volume 38:Issue 10(2018)
• Page Start: 3610
• Page End: 3617
• Publication Date: 2018-08
• Subjects: Al2O3/YAG DSE -- Directional solidification -- Eutectic microstructure -- Mechanical properties; Ceramic materials -- Periodicals; Composite materials -- Periodicals; Matériaux céramiques -- Périodiques; Composites -- Périodiques; Ceramic materials; Composite materials; Periodicals; Electronic journals; 666.05
• DOI: 10.1016/j.jeurceramsoc.2018.04.017
• Languages: English
• ISSNs: 0955-2219

Abstract

Abstract: Al2 O3 /Y3 Al5 O12 (YAG) directionally solidified eutectic (DSE) crystal was prepared by optical floating zone technique. Al2 O3 /YAG DSE consists of continuous entangled Al2 O3 and the YAG forming a three-dimensional networks structure. The volume fraction of porosity is ultra-low (0.013%) and the average equivalent diameters of most pores (>84%) are smaller than 4 μm. The Al2 O3 /YAG DSE shows excellent high-temperature elastic stiffness. The Young's modulus at 1500 °C maintains more than 85% of the value at room temperature. Bending strength exhibits excellent retention up to high temperature as well. High-temperature ball indentation testing shows plastic deformation involving dislocations and twinning, which predominantly occur in Al2 O3 phase, while the YAG phase is stable. Evaluation on Hv /E index predicts Al2 O3 /YAG DSE with moderate capability to accommodate damages. Our results highlight Al2 O3 /YAG DSE as excellent high-temperature structural materials.