Aluminium-copper-cullet metal composite: a secondary source of aluminium from waste materials

In this work, Aluminium composites were fabricated from recycled materials, using recycled Aluminium (Al) obtained from scrap door and window frames, copper (Cu) wire scrap and cullet powder (CP). The Al-Cu-CP metal composite was fabricated via stir casting method due to its simplicity and economic importance. The composite and the unreinforced Al were analysed for physical, mechanical and morphological properties. The analyses indicated that the chemical composition of the products covered all the initial components. The results of hardness tests were found to have improved significantly due to the impact of the reinforcement materials. The hardness increased from 40.625 HV of the unreinforced Al to 124.704 HV for Al-Cu-CP metal composite. The microstructural analysis of the composite revealed appreciable distribution of the reinforcement materials within the Al matrix. Evolution of new phases was also revealed which furthermore contributed immensely towards enhancing the strength of the composite. It is obvious that the properties of the Al-Cu-CP composite were relatively enhanced significantly. Thus, it could be used where high strength with less density composite is required such as automobile brake shoes and brake disc as a result of the upgraded mechanical properties

Physicomechanical properties of nanobiocomposite composed of polylactic acid and biogenic nano hydroxyapatite

In the current paper, nanobiocomposite consisting of polylactic acid (biodegradable) (PLA) and nanohydroxyapatite (bioactive) (n-HAP) extracted from bovine bone was fabricated through melt mixing and injection moulding technique for biomedical applications. Partially biogenic nanohydroxyapatite was obtained from bovine bone by hydrothermal method and calcination treatment without using of any chemicals/solvents. Physicomechanical properties of neat-PLA and PLA/n-HAP nanobiocomposite were evaluated using X-ray diffraction (XRD), universal testing machine (UTM) and scanning electron microscopy (SEM). XRD result showed that the intensity of n-HAP peaks increased in the nanobiocomposite as n-HAP-900 loading increased. Tensile strength decreased with increasing the n-HAP-900 loading from 56.78 to 48.25 MPa due to poor interfacial adhesion between neat-PLA and n-HAP. PLA/n-HAP with 1% loading exhibits tensile strength potential for bone implant application and can be promising biomedical materials for orthopedic applications