Design strategies for enhancing strength and toughness in high performance metal matrix composites: A review

Increasing application of lightweight, high performance metal matrix composites (MMCs) namely high-strength, high-toughness, across diverse industrial sectors, has led to a noticeable quest for the production of new lightweight MMCs (LWMMCs). Architectural design features of the LWMMCs revealed significant effects on the mechanical properties of the composites as the presence of the reinforcements did. Up to now most of the research projects have focused on the effect of different reinforcements and the design of the architectural features have not been considered widely by the researchers to control the mechanical properties. This paper explores the heterogeneous design configuration of LWMMCs to achieve simultaneous strengthening and toughening. However, aluminum matrix composites (AMCs) are highlighted for their weight reduction potential and enhanced performance in aerospace, electronics, and electric vehicles. In addition, it discusses the role of reinforcements and the intrinsic matrix design in determining the mechanical properties of these composites. Then it is revealed that the remarkable mechanical properties such as elevated strength, malleability, and fracture resilience, which are not found in traditional materials are attributed to the intricate interplay features including stress–strain gradient, geometrically necessary dislocations, and distinctive interfacial phenomena. In addition to the heterogeneous deformation-induced hardening effect, this article tries to reveal the strategic importance of energy dissipation as a means to increase toughness in LWMMCs by controlling the crack propagation and localizing deformation, while addressing the complexities associated with composite fabrication.