Microstructures, Properties and In Situ Toughening of Rapidly Solidified Al₂O₃/YSZ Composite Ceramics Prepared by Combustion Synthesis

Abstract:

The large-scale Al2O3/YSZ ceramic plates were prepared by combustion synthesis under high gravity, the ceramics were mainly composed of random-oriented rod-shaped grains, and within the rod-shaped grain aligned nano-submicron YSZ fibers were embedded. Compared to the high-performance directionally solidified ceramics, the hardness, flexural strength and fracture toughness of the eutectic ceramics obtained in the experiment increased by 40.7~55.1%, 9.6~26.0% and 172.0~240.0%, respectively. The increase in hardness and strength of the ceramics could be attributed to nano-submicron YSZ fibers and inter-phase spacing and the refinement of the eutectic grains; meanwhile, high-energy, large-angle boundaries between rod-shaped grains could introduce strong toughening mechanisms involving crack-bridging and pull-out of rod-shaped eutectics.

• Periodical: Key Engineering Materials (Volumes 368-372)
• Pages: 771-774
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.368-372.771
• Online since: February 2008
• Authors: Zhong Min Zhao, Long Zhang, Yi Gang Song, Wei Guo Wang
• Keywords: Combustion Synthesis (CS), Nanocrystalline, Rapid Solidification, Rod-Shaped Eutectics

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