Mechanical and Wear Characterization of Sodium Hydroxide–Treated Ficus Amplissima Natural Fiber Epoxy Composites

Natural fibers have gained popularity in composites because they are inexpensive, lightweight, and biodegradable. However, challenges such as poor bonding and high moisture absorption persist. This study addressed these issues by treating aerial roots of Ficus amplissima fibers (ARFAFs) with a 5% NaOH solution at various fiber weight percentages (5%, 10%, 15%, 20%, and 25%). The study found that alkali treatment improved the bond between the polymer matrix and the fibers, resulting in increased tensile, flexural, and impact strength, which improved from 44.76 to 46.71 MPa (4.36% improvement), from 59.38 to 63.12 MPa (6.29% improvement), from 85.66 to 92.22 J/m (7.66% improvement), respectively. Additionally, water absorption was reduced compared to untreated fibers. The tribological behavior of ARFAF composites was investigated using a pin-on-disc machine. The experiments were designed using the Taguchi method, and analysis of variance was conducted utilizing Minitab 19 software. Four factors were considered: fiber weight percentage, load, sliding speed, and sliding distance, each at three levels. Results revealed that the applied load was the most significant variable, contributing 41.72% to the sliding wear of the composites. Furthermore, a higher fiber weight percentage improved the wear resistance, resulting in a less mass loss.