Advanced liquid state processing techniques for ex-situ discontinuous particle reinforced nanocomposites: A review

Recent times, metal matrix composites (MMC) are considered as candidate materials for numerous applications such as aerospace, automotive and military industries due to improved properties over the conventional metals and alloys. Out of the different categories of metal matrix composites, discontinuous particulate reinforced composites are preferred for industrial applications due to low manufacturing cost. High fracture toughness, improved ductility and machinability characteristics support the selection of metal matrix nanocomposites (MMnC) over conventional composites for different applications. The majority of nanocomposites are produced through liquid state processing due to faster processing time and economy. However, the conventional liquid processing method leads to poor wetting of reinforced nanoparticles by molten metal that degrades the quality of the fabricated nanocomposite. This paper reviews some of the advanced liquid state processing techniques adopted for the improved wettable characteristics of nanoparticles and their uniform distribution in the metal matrix.