Abstract
<title>Abstract</title> <p>The growing demand for sustainable and high-performance engineering materials has promoted the utilization of agricultural waste-derived reinforcements in aluminium matrix composites. In this study, nanoscale Banana Peel Ash (BPA), synthesized via dehydration, calcination, and high-energy ball milling, was employed as an eco-friendly reinforcement in Al7075-T6 composites fabricated by the stir-casting process. The synthesized BPA was characterized using Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS), particle size analysis, and thermogravimetric analysis, which confirmed the formation of thermally stable nano-sized particles enriched with oxide-forming elements such as potassium, oxygen, calcium, magnesium, and silicon. The wear behaviour of the fabricated composites was investigated under dry sliding conditions, revealing a significant reduction in wear rate with increasing BPA content. SEM examination of worn surfaces indicated a transition from severe adhesive wear in the base alloy to mild abrasive wear in reinforced composites, characterized by shallow grooves, reduced delamination, and limited wear debris formation. Impact testing demonstrated enhanced energy absorption capability and improved resistance to crack initiation and propagation with BPA addition. SEM analysis of impact-fractured specimens revealed ductile fracture features, including dimples, tear ridges, and microvoid coalescence. Furthermore, immersion corrosion studies showed improved corrosion resistance due to the formation of stable protective oxide layers and uniform reinforcement distribution. The results confirm that nanoscale BPA is an effective, low-cost, and sustainable reinforcement for enhancing the wear, impact, and corrosion performance of Al7075 composites. The enhanced mechanical, tribological, and corrosion properties of the developed composites are potential candidates for applications in aerospace structural components, automotive parts, marine equipment, defence systems, lightweight machinery components, and other engineering sectors.</p>