铜包覆多壁碳纳米管增强铝基复合材料的制备及力学性能

采用化学镀的方法在碳纳米管表面镀覆一层铜纳米颗粒,旨在改善其与铝基体之间界面结合性能,从而提高复合材料最终的力学特性,用常压烧结与高温模压、热挤加工相结合的工艺制备碳纳米管增强铝基复合材料,通过X线衍射仪、扫描电子显微镜、透射电子显微镜等对经过表面化学镀的碳纳米管粉末和复合材料的结构与性能进行表征测试。结果表明:随着碳纳米管质量分数的增加(0~4.0%),复合材料的硬度逐渐上升,抗拉强度先升高后下降;当质量分数为3.5%,分别可达到207.74HB和453.84 MPa,比纯铝提高了230.6%和326.9%,相比不经任何处理直接添加碳纳米管制备的复合材料提高了47.5%和23.55%。

Preparation and mechanical properties of copper coated multi-walled carbon nanotubes reinforced aluminum matrix composite

In order to improve the interface performance between carbon nanotubes(CNTs)and aluminum matrix,and increase the final mechanical properties of composite material,carbon nanotubes coated with copper were prepared by chemical plating method. Carbon nanotube reinforced aluminum matrix composites were prepared by powder metallurgy method combining with pressureless sintering,mould pressing and hot extrusion. The powders after chemical plating were analyzed by X-ray diffraction(XRD),scanning electron microscope(SEM)and Transmission electron microscope(TEM). The mechanical properties of composite were investigated by universal material testing machine and Brinell hardness test. The fracture surfaces of the composites were characterized by SEM. The results show that with the increase of CNTs addition(0~4.0%),the hardness of composites gradually increases,while the tensile strength increases firstly and then decreases. The hardness and tensile strength of the composite reach 207.74HB and 453.83 MPa at3.5%CNT content,increasing by 230.6% and 326.9% than those of pure Al sample,and increasing by 47.5% and 23.55% than those of the composites without treatment.