The effects of different types and ratios of reinforcement, and machining processes on the machinability of Al2024 alloy nanocomposites

Abstract

In the presented study, aluminum metal matrix nanocomposites reinforced with SiC and B4C, with different reinforcement ratios (0–4 wt%), have been prepared using the powder metallurgy method. The main objective of this study is to investigate the effect of different reinforcements and reinforcement amounts on the machinability of metal matrix nanocomposites using different machining processes (WEDM and CNC milling). The surface morphologies of the samples were investigated before and after machining using scanning electron microscopy and chemical analysis of the samples was obtained using EDX and X-ray diffraction. The surface hardness, roughness, and metal removal rate (MRR) before and after machining were examined to investigate the effect of the machining process on the surfaces of the samples. According to the results of the study, the hardness value of the nanocomposite containing 4% B4C by weight (195.6 HB) increased by approximately 90% compared to the hardness value of the pure Al2024 alloy (101.6 HB). After both machining processes, the hardness values of all nanocomposites decreased. In addition, the tensile strength values of the nanocomposites containing 2% B4C and SiC by weight are 392.8 MPa and 377.7 MPa, respectively, while the tensile strength value of the pure Al2024 alloy is 201.7 MPa. After both machining processes, the hardness values of all nanocomposite samples decreased. While the MRR values decreased with the increase in the reinforcement amount of the nanocomposites after machining, the SR values decreased.