Effect of Magnesium Addition of Aluminum Matrix Composites CNT Reinforced Using Stir-Squeeze Casting Method

Aluminum matrix composites (AMCs) reinforced with carbon nanotubes (CNTs) are widely developed nowadays because they have superior properties. One method of manufacturing AMCs is stir-squeeze casting. This study investigated the effect of magnesium addition on 1% wt CNT reinforcement. Aluminum matrix composites made using Aluminum 6063 reinforced with 1% wt CNT added magnesium with variations (0%, 2%, 4%, 6% wt) were made by a casting method which combines stir-casting at 350 Rpm for 2 minutes with squeeze-casting at a pressure of 10 Mpa for 75 seconds, cast on a metal mold heated at 450°C and an AMC casting temperature of 750°C . The results of CNT-reinforced AMC casting were studied for physical properties, namely porosity and density, mechanical properties, namely tensile strength and hardness, and microstructure characterization, namely OM and SEM. The results showed that adding magnesium can reduce porosity and increase density. The results of hardness testing also show that increasing Mg can increase hardness, and the highest hardness value is 48.8 HV at the addition of 6% Mg, with an increase of 74% from the raw material. The microstructure observation results show that adding Mg functions as a wetting agent, which causes CNTs to be evenly distributed and no accumulation occurs.