片状粉末法制备碳纳米管/铝复合材料的组织特征及性能调控

Microstructure Characteristics and Property Control of Carbon Nanotube/Aluminum Composites Prepared by the Flaky Powder Method

本文利用片状粉末法中片状铝粉末大比表面积优势,结合粉末冶金法成功制备了碳纳米管/铝复合材料,实现了碳纳米管的低结构损伤和在铝基体中的良好分散。但片状铝粉表面自发生成的氧化铝薄膜阻碍了碳纳米管与铝的直接结合。由于粉末冶金低的制备温度,这种碳纳米管-氧化物-铝之间难以形成强的化学键合,复合材料在拉伸后直接在混合界面上破坏,导致复合材料相比基体合金强度不增反降。通过增加片状粉末厚度进而减小其表面的氧化物以及结合添加镁元素的方法,大幅增加界面结合强度,复合材料的屈服强度和抗拉强度相比基体出现高效提升。

In this paper,carbon nanotube/aluminum composites were successfully prepared by taking advantage of the large specific surface area of flake aluminum powder using the flake powder method,and low structural damage to carbon nanotubes and good dispersion in an aluminum matrix were achieved.However,the natural existence of aluminum oxide film on the surface of aluminum powder prevented the direct bonding of carbon nanotubes and aluminum.Due to the low preparation temperature of powder metallurgy,it is difficult to form a strong chemical bond between the carbon nanotube,oxide and aluminum,and the composites are directly destroyed at the mixed interface after tensile testing,resulting in a decrease in the strength rather than an increase compared with the matrix alloy.By increasing the thickness of the flaky aluminum powder to reduce the oxide on its surface and combining it with the addition of magnesium,the interfacial bonding strength is greatly increased,and the yield and tensile strength of the composite are significantly improved compared with those of the matrix.