CNTs/Al5083复合材料力学性能及增强机制

采用高能球磨和冷轧工艺制备出3%(质量分数)碳纳米管增强Al5083复合材料。利用SEM,TEM观察球磨后复合粉末表面形貌,采用拉曼光谱和XRD对复合粉末和成型后的材料进行物相分析。最后测试了复合材料的力学性能。结果表明:在球磨1.5h的复合粉体中CNTs分散均匀,结构较完整,部分嵌入Al基体中并结合良好。冷压烧结并冷轧成型后的复合材料力学性能表现优异,球磨1.5h下,复合材料抗拉强度和屈服强度分别达到278MPa和247MPa,断裂延伸率为0.07,硬度HV达到95。将热不匹配模型与奥罗万模型所预测的屈服强度与实验值进行对比,结果表明CNTs/Al5083复合材料符合奥罗万机制。

M echanical Property and Enhancement Mechanism of Aluminum 5083 Composites with Carbon Nanotubes

The composite materials of 3% (mass fraction)carbon nanotubes(CNTs)/Al5083 were fabri‐cated by high‐energy ball milling and cold rolling .The surface morphology of the composite powder of ball milled was observed using SEM and TEM ,the phase of composite powder and composite material w ere analyzed by Raman spectrum and XRD .Finally ,the mechanical properties of composite material were tested .The results show that ,the CNTs have a good structure and are well‐distributed in the for 1 .5h milled aluminum matrix .The composite material exhibits high strength for the tensile strength of 278MPa ,yield strength of 247MPa and elongation rate of 0 .07 ,Vickers hardness of 95 .Compared with the predicted value of yield strength by thermal mismatch model and Orowan model ,the experi‐ment value indicates that the mechanism of CNTs/Al5083 accords with Orowan mechanism .