Enhancing mechanical, structural and wear properties of Al-Mg-Si-Ni-based biocomposites: Additives of hybrid high-temperature materials and bamboo leaf particulates

We studied the effects of hybrid bamboo leaf particulate (BLp), alumina (Al 2 O 3 ) and zirconia (ZrO 2 ) concentrations on structural, mechanical, physical and wear properties of Al-based biocomposites. BLp was subjected to alkali and thermal treatment to improve its surface morphology, distribution and interaction with the Al-based alloy. The composites were made using a double layer feeding stir casting method, with reinforcements added at 2 and 4 wt% concentrations and hybrid concentrations after carbonisation. The BLPs were characterized using Fourier transform infrared (FTIR) spectroscopy, X-ray fluorescence (XRF) and scanning electron microscope/energy dispersive x-ray (SEM/EDX). The corrosion study of Al-7Mg-3Si-1.5Ni/Al 2 O 3 /ZrO 2 /BLA biocomposites was conducted in a 1 M HCl solution, and the effects of solution temperature and immersion time were investigated using weight loss measurements at 303 K and immersion times of 1, 2, 4, 6, 8 and 10 h. FTIR spectroscopy revealed changes in BLp functional groups and molecular structure following treatment, whereas SEM and OM analysis revealed changes in particle distribution and elemental composition, indicating that the thermochemical treatment altered the crystallinity, distribution and orientation of particulate matter while improving particle surface roughness and mechanical interlocking matter. The mechanical properties of the biocomposites showed improvements in ultimate tensile strength, hardness, impact and wear resistance, with a maximum tensile strength of 235.17 MPa, hardness of 110.6 BHN, impact of 62.3 J, and a lower wear rate of 2.82 × 10 −4 mm 3 /mm (64.08 % decrease). Density and porosity analysis revealed changes in biocomposites structure and compaction after treatment and reinforcement, with hybrid Al 2 O 3 /ZrO 2 /BLA reinforced Al-based biocomposites recording the highest density value of 2.80 g/cm 3 due to increased wettability and their porous-free structure. The difference in theoretical and experimental density values indicates the presence of porosity, with % porosity values ranging from 0.4 to 1.11. Reinforcements improved particle dispersion in biocomposites, but their effect was further enhanced in hybrid and varied systems. The hybrid Al-7Mg-3Si-1.5Ni/Al 2 O 3 /ZrO 2 /BLA biocomposites outperformed single additions of Al 2 O 3 , ZrO 2 and BLA. This suggests that using alkali-treated BLp and hybrid plant-based reinforcing with high-temperature metallic materials (Al 2 O 3 and ZrO 2 ) can significantly improve the mechanical, structural and wear properties of Al-based biocomposites. • The effects of hybrid BLp, Al 2 O 3 , and ZrO 2 concentrations on the structural, mechanical and wear properties of Al-based biocomposites were studied. • BLp was subjected to alkali and thermal treatment to improve its surface morphology, distribution, and interaction with the Al-based alloy. • Composites were made using double-layer feeding stir casting method, with reinforcements added at 2 and 4 wt% and hybrid concentrations. • SEM, OM and FTIR analysis revealed changes in functional groups, particle distribution, crystallinity, orientation, elemental composition and surface roughness. • The biocomposites improved in UTS (235.17 MPa), hardness (110.6 BHN), impact (62.3 J), and a lower wear rate of 2.82 x 10 -4 mm 3 /mm (64.08 % decrease).