Revealing the compatible deformation mechanism of metal particles reinforced aluminum matrix composites

In this work, the hot deformation behavior of Be particles reinforced Aluminum matrix composites (AMCs) was studied, and similar experiments were conducted on the AA2024 matrix and SiC/AA2024 composites with comparable reinforcement volume fraction to compare the differences in hot deformation processes among different types of reinforcements. The AA2024 matrix experienced overburning at 550 °C, while the Be/AA2024 composite did not fail due to overburning because of its lower proportion of Al grain boundaries. The SiC/AA2024 composite failed during the high-temperature compression process due to its extremely low plasticity. The introduction of Be particles only increased the deformation activation energy of the Be/AA2024 composite (281 kJ/mol) by 3.4 % compared to the AA2024 matrix (272 kJ/mol), whereas the deformation activation energy of the SiC/AA2024 composite (398 kJ/mol) increased by 46.3 % compared to the AA2024 matrix. The microstructure of the deformed AA2024 matrix is primarily composed of deformed grains, while significant dynamic recrystallization (DRX) occurred in the Al matrix of both the Be/AA2024 and SiC/AA2024 composites. Because Be particles can also deform, they underwent dynamic recrystallization, alleviating stress concentration at the interface and maintaining the integrity of the interface.