Selective laser melting (SLM) is a near-net-shape time- and cost-effective manufacturing technique, which can create strong and efficient components with potential applications in the aerospace industry. To meet the requirements of the growing aerospace industrial demands, lighter materials with enhanced mechanical properties are of the utmost need. Metal matrix composites (MMCs) are extraordinary engineering materials with tailorable properties, bilaterally benefiting from the desired properties of reinforcement and matrix constituents. Among a wide range of MMCs currently available, aluminum matrix composites (AMCs) and titanium matrix composites (TMCs) are highly potential candidates for aerospace applications owing to their outstanding strength-to-weight ratio. However, the feasibility of SLM-fabricated composites utilization in aerospace applications is still challenging. This review addresses the SLM of AMCs/TMCs by considering the processability (densification level) and microstructural evolutions as the most significant factors determining the mechanical properties of the final part. The mechanical properties of fabricated MMCs are assessed in terms of hardness, tensile/compressive strength, ductility, and wear resistance, and are compared to their monolithic states. The knowledge gained from process–microstructure–mechanical properties relationship investigations can pave the way to make the existing materials better and invent new materials compatible with growing aerospace industrial demands.
Selective laser melting of hybrid ex-situ/in-situ reinforced titanium matrix composites: Laser/powder interaction, reinforcement formation mechanism, and non-equilibrium microstructural evolutions
