钛对碳纳米管增强铝基复合材料组织与性能的尺寸效应

通过粉末冶金的方法,制备了致密和较高强度的CNT/Al复合材料,并系统地研究了在制备粉末阶段时引入不同粒径的钛粉后,对复合材料的组织结构与力学性能的影响。结果表明,在一定范围内,钛颗粒尺寸与制备的CNT-Ti/Al复合材料力学性能成反比。当加入的钛颗粒粒径为80 nm时,CNT-Ti/Al复合棒材力学性能最佳。其主要原因包括两个方面:一是钛颗粒有助于碳纳米管的分散,同时自身作为一种第二相强化基体;二是制备过程的热反应,使复合材料组织中生成了一种核壳结构,极大地增强了其界面结合与碳纳米管的载荷转移。

Dimension effect of Ti powder size on evolution of microstructure and mechanical properties of CNT/Al composites

CNT/Al composites were prepared by powder metallurgy with high density and strength, the effects of different sizes of titanium powder on microstructure and mechanical properties of the composites were systematically studied. The results show that mechanical properties of the CNT-Ti/Al composites are inversely proportional to the particle size of the Ti powders. The CNT-Ti/Al composite rod has best mechanical properties with added Ti powder with particle size of 80 nm. These results can be attributed to the Ti powder not only circumvents CNTs dispersion burden, but also plays as second phase particles that enhance the strength of matrix. Besides, owing to the heat reaction during the preparation process, a core-shell structure is formed, which improves the interface bonding and the load transfer efficiency of CNTs.