In this study, the microstructure and mechanical properties of extruded aluminium (Al6061) based composites reinforced with multiwall carbon nanotubes (MWCNTs) were investigated. Composites with varying volume fractions of MWCNTs (1 vol% and 3 vol%) were fabricated initially using high energy ball milling, followed by compaction and sintering. Hot extrusion was carried out for the developed composites at different extrusion temperatures, extrusion ratios and die angles. SEM analysis of the extruded composites showed good dispersion of the MWCNTs within the Al matrix alloy. Improvements in micro-hardness and compressive strength were observed in the extruded composites with 3 vol.% MWCNTs without any deterioration in elongation. In addition, the workability behaviors of the composites were investigated by a cold upsetting test. The pore reopening tests were performed to confirm the closure of pores after the extrusion and to further analyze the densification of the composites. The results for the densification process based on extrusion confirmed that the pores turned into spherically closed pores. For typical cases, the pores did not reopen even after increasing the strain therefore, additional forming was possible up to large deformations.

在这项研究中，研究了多壁碳纳米管（MWCNTs）增强的挤压铝（Al6061）基复合材料的微观结构和力学性能。首先使用高能球磨制备出具有不同体积分数的MWCNT（1％（体积）和3％（体积））的复合材料，然后进行压实和烧结。在不同的挤出温度，挤出比例和模头角度下，对已开发的复合材料进行热挤出。挤出复合材料的SEM分析表明，MWCNT在Al基合金中分散良好。在具有3体积％的MWCNT的挤出复合物中观察到显微硬度和抗压强度的改善，而伸长率没有任何降低。此外，通过冷up试验研究了复合材料的可加工性行为。进行孔重开测试以确认挤出后孔的闭合并进一步分析复合材料的致密化。基于挤出的致密化过程的结果证实，孔变成球形封闭孔。对于典型的情况，即使在增加应变后，孔也不会重新打开，因此，可能会出现较大的变形，进而形成附加的形状。