Author: Guorui Zhao (一作), Jixin Chen, Yueming Li, Liya Zheng, Jialin Li, Xiaohui Wang, Meishuan Li

Journal:Journal of the European Ceramic Society

DOI：10.1016/j.jeurceramsoc.2016.08.001

Abstract / 摘要

Abstract(#br)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 P6 3 /mmc. The lattice parameters are a=b=3.424Å, c=17.291Å, 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 YAl 3 C 3 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 276GPa (85% of that at room temperature) at 1500°C, suggesting that YAl3C3 is a promising lightweight high temperature structural material. 

Keyword / 关键词

Layered carbide;YAl3C3;Crystal structure;Mechanical properties;High temperature stiffness