碳纳米管增强2024铝基复合材料的力学性能及断裂特性

为了研究碳纳米管对铝基复合材料性能的影响,采用冷等静压、热挤压方法制备了质量分数1.0%的多壁碳纳米管增强2024Al基复合材料.采用扫描电镜、透射电镜和拉伸试验对复合材料的显微组织进行了观察和分析,并对其力学性能进行了测试.结果表明,碳纳米管均匀地分布在复合材料中,碳纳米管和铝基体的界面结合良好,没有发现界面产物Al4C3的形成;复合材料的断口上存在大量的撕裂棱,韧窝,并涉及碳纳米管的拔出或拔断与桥接,与2024Al基体材料相比,复合材料的硬度、弹性模量和抗拉强度显著提高,同时复合材料的延伸率却并不下降.碳纳米管的加入可以显著提高铝基复合材料的力学性能.

Mechanical properties and fracture characterization of 2024Al composite reinforced with carbon nanotube

In order to investigate the effect of carbon nanotube (CNT) on the properties of Al matrix composite,2024Al matrix composite reinforced with 1. 0 wt. % multi-wall carbon nanotubes (MWNTs) was fabricated by cold isostatic pressing and hot extrusion techniques. Mechanical properties of the composite were measured by a tensile test,and the microstructure was observed using FESEM. Results show that carbon nanotubes (CNTs) were dispersed uniformly in the matrix,the interfaces of the CNTs and the Al matrix bonded well,no reaction product of Al-C was generated during the fabrication of the composite. The fracture surfaces of the composite involved in a mass of tear-ridge and shallow dimple morphologies,as well as the bridging and pulling out/ breakage of CNTs. The hardness,the Young’s modulus and the tensile strength of the composite were enhanced markedly in relation to those of the matrix materials under the same process,respectively,meanwhile,the elongation of the composite was not decreased. It is concluded that the addition of CNT into the Al matrix composite can obviously improve its properties.