Mg-ZrO₂ nanocomposite: Relative effect of reinforcement incorporation technique

In this study, ingot metallurgy and powder metallurgy processes were used to incorporate 0.2 and 0.7 vol% of nano-size ZrO₂ particles reinforcement to develop magnesium nanocomposite. Both of the processing methods led to reasonably fair reinforcement distribution, substantial grain refinement and minimum porosity in the nanocomposites. Strengthening effect of nano-ZrO₂ reinforcement in the magnesium matrix was greater when incorporated using the ingot metallurgy process. The matrix ductility and resistance to fracture were significantly improved due to the presence of nano-ZrO₂ reinforcement when incorporated using the powder metallurgy process. Tensile fracture surfaces revealed that the less-ductile cleavage fracture mechanism of hexagonal close packed magnesium matrix has changed to more ductile mode due to the presence of nano-ZrO₂ particles in all the processed nanocomposites.