Investigation of aluminum metal matrix composite fabrication processes: a comparative review

Aluminum alloys are widely used in industry because of their superior mechanical qualities and high specific strength-to-weight ratio. Al-matrix composites (AMC) may identify the newly synthesized material because it has the mechanical properties of pure aluminum alloys with reinforcement from a variety of ceramics. Matrix materials have included aluminum alloys, with ceramic reinforcements including aluminum oxide (Al₂O₃), magnesium oxide (MnO), graphene nanoplatelets (GNPs), boron carbide (B₄C), silicon carbide (SiC), graphite (Gr), fly ash (FA), etc. The best, most practical, and most cost-effective way to create the composites is by the stir casting process. The review focuses on the two-step stir-casting process for AMCs production. Reinforcement pre-heating temperature, injection rate, porosity, wettability, stirrer structure, stirring time and speed, purge, pouring temperature, solidification rate, and mold temperature are examined to optimize the casting process. Optimal conditions include preheating particles at 200–500°C for 30–60 min, maintaining a feeding rate of 8–10 mg/min, stirring speeds of 700–800 rpm for 10–40 min, and using a 30-degree to 60-degree impeller-blade angle. Emerging trends suggest enhancements such as microwave heating, ultrasonic probe usage, inert environment incorporation, and electromagnetic stir casting for improved wettability and uniformity.