Determination of Some Selected Mechanical Properties of Recycled Aluminium Alloy Modified with Micro- And Nano-Sized Additives

Abstract

The growing demand for sustainable materials has intensified interest in recycled aluminium alloys, which present a more energy-efficient alternative to primary aluminium production. However, recycled aluminium typically suffers from diminished mechanical properties due to the presence of impurities and microstructural irregularities. This study explored the influence of nano- and micro-sized reinforcements (black powder, graphite, and waste glass) on the mechanical performance of recycled aluminium alloys. Aluminium was mixed with 6%, 8%, and 10% weight fractions of each reinforcement, and processed using the sand casting technique to produce composite samples. The composites were evaluated for their physical, metallurgical, and mechanical properties. Results indicate that nano-scale reinforcements enhanced hardness, impact strength, and tensile strength relative to their micro-scale counterparts. The highest hardness (84.36 HV) was achieved with 10% nano-glass (GL10), while 8% nano-black powder (BP8) yielded the highest impact strength (18.67 J). Additionally, 10% nano-graphite (G10) produced the highest tensile strength (103 MPa), surpassing the micro-reinforced equivalent (78 MPa). These findings confirm the potential of nano-reinforced recycled aluminium alloys for use in high-performance engineering applications.