Metal Matrix Nanocomposites: A Brief Overview

Abstract

The need for lightweight materials is increasing at a faster rate in the engineering field. It demands materials with high strength, low weight, and properties like ductility and formability which are required for easier processing of the material. When conventional pure metals and alloys failed to meet this demand, many researchers turned their attention toward developing composites. Composites can be fabricated from metal, polymer, and ceramic as base materials which are known as metal matrix composites (MMC), polymer matrix composites (PMC), and ceramic matrix composites (CMC), MMC are of special importance due to properties like strength, stiffness, and formability which are difficult to obtain from PMC and CMC. Even though conventional composites with micron-size reinforcement have enhanced certain properties like strength, hardness, and wear resistance, it deteriorated other desirable properties like ductility. To overcome these limitations of micro-composites, a new category of materials known as nanocomposite has been developed. Nano composites are materials that contain nano-scale reinforcement in different forms. This review article summarizes the recent progress in the field of metal matrix Nano composite (MMNC). Methods of fabrication which are applicable for metal alloys and micro-composites are mostly not suitable for nanocomposite fabrication, the recently developed fabrication process which are applicable for MMNC’s are discussed in this article. The effects of added nano reinforcement on the microstructure are also discussed with suitable examples. Enhancements in mechanical, tribological, and physical properties are explained in depth with the help of recently published data. Strengthening mechanisms are described with the help of empirical relations. Although industrial applications of metal matrix nano composites are limited due to the ongoing developments in this field, a few important potential application areas are also discussed at the end of this article.