Developing a technology for obtaining an aluminum matrix composite reinforced with multi-walled carbon nanotubes

The paper presents the results of studying the effect of the addition of multi-walled carbon nanotubes (MWCNTs) on the physical and mechanical properties of aluminum alloys AK9 and AK12 obtained by using a stir casting and suspension casting technologies. When conducting experiments on stir casting MWCNTs, limitations were revealed, such as the difficulty of their uniform distribution in the melt, as well as a decrease in efficiency when increasing the thickness of the cast piece and/or performing sand-mold casting. A comparative analysis of the samples was carried out, which showed that the use of multi-walled carbon nanotubes (0.1 wt. %) as micro-additives leads to an increase in the tensile strength of the composite by at least 15% provided their uniform distribution. However, at increased casting thickness, samples obtained by using a suspension casting technology demonstrate higher mechanical properties. In addition, the suspension casting technology enables an increased productivity without equipping the furnace with a stirring device.