Effect of high temperature compressive deformation on microstructure and mechanical characteristics of closed cell AA6061-B4C-Gr nanoparticles hybrid composite foam

This study investigated the behavior of B4C-Gr nanoparticles filled aluminum alloy 6061 (AA 6061) syntactic foam under high temperature compressive deformation. The experiment examined varied strain rates (ranging from 0.001 to 1 s−1) and temperatures (changing between 100 to 250°C). Calcium carbonate powders are utilized as blowing agents in this process (CaCO3 3 wt% of composite with a 40–50 µm size). As leading and secondary reinforcing agents, boron carbide (B4C 0, 1, 3, and 6 wt% with 25 µm) and graphene nanoparticles (0.5 wt% with particle size 1–25 µm and thickness 1–15 nm particle size) were used. The amounts of densification strain, energy absorption capacity, and plateau stress were determined by analyzing stress-strain curves obtained under different conditions of temperature, strain rate, and relative density. The plateau stress diminishes with temperature regardless of the strain rate. The densification strain stays constant regardless of the strain rate, but slightly rises with temperature. It was determined that the plateau stress and energy absorption capacity both increased with increasing strain rate and relative density. Lower relative densities were more affected by temperature than higher ones by both plateau stress and energy absorption capacity. While the relative density remained unchanged, the densification strain remained rather consistent throughout a range of strain rates. •The hybrid composite foams are produced by combining AA 6061 with B4C and Gr nanoparticles, ensuring that the nanoparticles are uniformly dispersed.•Explored the characteristics of microstructure and compressive properties and established empirical correlations among modulus, strength, energy absorption, and densification strain.•An in-depth examination of the compressive strength and energy absorption capabilities of AA 6061 hybrid composite foams, with a focus on how these properties are influenced by temperature and strain rate.•Significant improvements in strength and modulus were seen when B4C and Gr nanoparticles were combined.