ZM1 magnesium alloy reinforced by carbon nanotubes using an improved casting process

Melt processing is a promising process to fabricate Mg–CNTs (carbon nanotubes) composites with high performance and large dimensions. In this work, the liquid-mixing technique and ball-milling processes as well as the stirring casting method were used to prepare ZM1-1.0CNTs-L and ZM1-1.0CNTs-B composites, respectively. The composites were studied using optical microscopy (OM), Raman spectroscopy, scanning electron microscope (SEM), transmission electron microscope (TEM) and room-temperature tensile test. The results show that the yield strength (YS), ultimate tensile strength (UTS), elongation and microhardness values of the ZM1-1.0CNTs-L composite are improved by 37.3%, 29.6%, 37.0% and 33.3%, respectively, compared with those of ZM1 alloy. The uniform dispersion of CNTs as well as the strong interfacial bonds with the Mg matrix is the main reason for the significant improvement in mechanical properties of the as-cast composite. Liquid mixing combined with the stirring casting method is favorable to fabricate Mg–CNTs composite with high mechanical properties.