Development of anti-corrosion, structural, and optoelectronic potential of Capsicum annuum-Doped AA6063 alloy for marine applications

Abstract

The study explores the potential of incorporating pepper waste as a reinforcement material in aluminium AA6063 composites, with focussing on the morphological, mechanical, electrochemical, and optoelectric properties. Pepper wastes, including stalks and seeds, were carbonised, pulverized, and sieved to yield 75 μm particulates. These were mixed with molten AA6063 alloy via stir casting, with the pepper content ranging from 0% to 25% by weight. The composites were characterised using hardness testing, electrochemical evaluation, optoelectrical analysis, and morphological analysis. Hardness tests revealed that the 25% pepper-reinforced sample exhibited the highest hardness value of 37 HRB, a 31.7% increase over the control sample. Electrochemical evaluations showed significant improvements in corrosion resistance, with the corrosion potential (Ecorr) of the 25% pepper-reinforced sample reducing to −0.59 V and the corrosion rate decreasing to 7.69 mm/yr. Optoelectrical testing indicated enhanced conductivity in samples with higher pepper content, with the 25% reinforcement achieving a conductivity of 0.1979 (Ωm)⁻1. Morphological tests, such as SEM and XRD, revealed the uniform distribution of pepper particles and the occurrence of several phases that contribute to the composite's improved properties.