In situ synthesis, structure, and properties of bulk nanolaminate YAl₃C₃ ceramic

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• 作者：Guorui Zhao^a ; ^b ; Jixin Chen^a ; ^{jxchen@imr.ac.cn" class="auth_mail" title="E-mail the corresponding author} ; Yueming Li^a ; ^b ; Liya Zheng^a ; Jialin Li^a ; Xiaohui Wang^a ; Meishuan Li^a
• 关键词：Layered carbide ; YAl3C3 ; Crystal structure ; Mechanical properties ; High temperature stiffness
• 刊名：Journal of the European Ceramic Society
• 出版年：2017
• 出版时间：January 2017
• 年：2017
• 卷：37
• 期：1
• 页码：83-89
• 全文大小：1980 K

文摘

Polycrystalline YAl₃C₃ ceramic was fabricated by an in situ hot-pressing process using YH₂, Al, and C powders as starting materials. The crystal structure of YAl₃C₃ was determined by X-ray diffraction and ab initio calculations to be a hexagonal space group P6₃/mmc. The lattice parameters are a = b = 3.424 Å, c = 17.291 Å, and the atomic positions are Y at 2a (0, 0, 0), Al1 at 2d (1/3, 2/3, 3/4), Al2 at 4f (1/3, 2/3, 0.138), C1 at 2c (1/3, 2/3, 1/4), and C2 at 4f (1/3, 2/3, 0.6045). The reaction synthesis path for YAl₃C₃ was presented. Microstructure observations revealed that YAl₃C₃ ceramic had plate-like grain morphology. The elastic, mechanical and thermal properties of YAl₃C₃ were investigated. Most significantly of all, the Young’s modulus of YAl₃C₃ could retain 276 GPa (85% of that at room temperature) at 1500 °C, suggesting that YAl₃C₃ is a promising lightweight high temperature structural material.