Mechanical, fatigue and creep behavior of varying angle stacked bambus hampi hybrid fiber and nelumbonucifera cellulose toughened vinyl ester composites

This study investigated vinyl ester composites reinforced with cellulose from Nelumbo nucifera and Bambus hampifiber, fabricated using a standard stacking sequence (90°/45°/90°/45°). The effect of 3-aminopropyltrimethoxysilane surface treatment and fiber stacking on load-bearing, fatigue, and creep performance was examined. Among the composites, MP5 (40 vol.% fiber, 2 vol.% cellulose) exhibited the best overall mechanical performance, achieving tensile, flexural, and impact strengths of 165.3 MPa, 144.5 MPa, and 4.7 J, respectively, and sustaining up to 29,324 cycles at 25% UTS under fatigue. In contrast, MC6 (4% cellulose) showed the highest creep resistance, with minimal creep strain (0.0033 at 5000 s; 0.0219 at 10,000 s; 0.0459 at 15,000 s) and maximum hardness (99 Shore-D). Scanning electron Microscopic (SEM) analysis revealed that interfacial adhesion, crack propagation dynamics, and fracture morphology were the critical factors governing the mechanical performance of the composites.