Investigation of yttria-doped alumina nanocomposites reinforced by multi-walled carbon nanotubes
Investigation of yttria-doped alumina nanocomposites reinforced by multi-walled carbon nanotubes
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DOI：
10.1016/j.ceramint.2014.01.156
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发表时间：
2014-08-01
影响因子：
5.2
通讯作者：
Zhu, Yanqiu
中科院分区：
文献类型：
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作者：
Ahmad, Iftikhar;Islam, Mohammad;Zhu, Yanqiu
采用热压法制备了2wt%IsIDATCNTs增强Y2 O3掺杂Al 2 O3纳米复合材料。研究了少量Y2 O3（300 ppm）对碳纳米管增强Al 2 O3的显微结构和力学性能的影响。所得的Y2 O3掺杂的Al 2 O3-CNT纳米复合材料显示出接近理论密度（> 99%），具有令人惊讶的5倍细晶粒尺寸，并且与在相同实验条件下制备的纯Al 2 O3相比，断裂韧性（40%）、弯曲强度（20%）和硬度（18%）有显著改善。Y2 O3的加入提高了基体的致密度，消除了残余缺陷，并在纳米复合材料的晶界处形成了YAG（钇铝石榴石）颗粒。亚微米YAG颗粒与CNT一起促进了Al 2 O3基体形成细晶微观结构并改变了断裂模式，从而导致更高的韧性和其他机械性能。改善的机械性能允许Y2 O3掺杂的Al 2 O3-CNT纳米复合材料用于承载结构中的应用。(C)2014 Elsevier Ltd和Techna Group S.r.l. All rights reserved.
Nanocomposites of Y2O3 doped Al2O3 reinforced with 2 wt% IsIDATCNTs were fabricated by hot-pressing. The influence of a small Y2O3 addition (300 ppm) on the microstructure and mechanical properties of CNT-reinforced Al2O3 was investigated. The resulting Y2O3 doped Al2O3-CNT nanocomposites showed near theoretical densities ( > 99%) with an astounding 5 times finer grain size and substantial improvements in the fracture toughness (40%), flexural strength (20%) and hardness (18%) than pure Al2O3, prepared under identical experimental conditions. The Y2O3 addition improved the density of the matrix, eliminated the residual flaws and formed YAG (yttrium aluminium garnet) particles at the grain boundaries in the nanocomposites. The submicron YAG particles, together with the CNTs, promoted the Al2O3 matrix to form fine-grained microstructures and altered the fracture mode, thus leading to higher toughness and other mechanical properties. The improved mechanical properties allows for the Y2O3 doped Al2O3-CNT nanocomposites to be used for applications in load bearing structures. (C) 2014 Elsevier Ltd and Techna Group S.r.l. All rights reserved.