Physical properties of rice husk silica/alumina reinforced aluminium alloy matrix composite produced by cold compaction

• Main Authors: Kamaruddin, Nor Asmalinda, Nasir, Nurul Fitriah, Abdul Latif, Noradila, Roslan, Mohammad Fikrey, Mohd Joharudin, Nurul Farahin
• Format: Conference or Workshop Item
• Language: English
• Published: 2024
• Subjects: T Technology (General)
• Online Access: http://eprints.uthm.edu.my/11159/1/P16615_3fa867d0c8a8d0a1abf61b605f10eda1%208.pdf; http://eprints.uthm.edu.my/11159/; https://doi.org/10.1063/5.0182817

Many researchers are presently investigating the hybridization of aluminium chips due to commercial value, improved properties, and potential applications in aircraft, vehicles, and marine vessel production technologies, as well as to obtain more benefits, such as improved performance, cheaper prices, and less environmental impact. This research examines the effect of alumina (Al2O3) and rice husk silica (RHA) as reinforcement on the recycled aluminium alloy (AA7075) chip using the cold compaction process, in which the sample is compressed in a die using a hydraulic press. The aluminium AA7075 chip was reinforced with i.e., 0.5 wt.%, 3.0 wt.%, 5.5 wt.%, 8.0 wt.% and 10.5 wt.% at 63 μm size of RHA, and alumina powder at the sizes of 1.0 μm, 5.0 μm and 35.0 μm. The microstructure images show the random arrangement and various sizes of Al alloy chips in these matrix composite. The density for the sample 0.5RHA/Al2O3 reinforced AA7075 with a particle size of 35.0 μm of Al2O3 has the highest density at 2.5654 g cm-3, while the sample 3.0 RHA/Al2O3 reinforced AA7075 with a particle size of 1.0 μm of Al2O3 has the lowest of density at 2.3522 g cm-3. The porosity and water absorption were inversely proportional to the density. The porosity and water absorption increased until 3.0 wt.% of RHA and decreased to 10.5 wt.% of RHA. The increment of reinforcement composition causes an increase in the porosity due to clustering and pore nucleation between the matrix and reinforcement. However, the water absorption level corresponds with the presence of porosity inside the specimen. Based on investigation, the combination of agro waste and synthetic reinforcement can improve the properties of AMC