Characterization and static responses of partially biodegradable hybrid composites: Experimental and numerical analysis

The flexural responses under different loading of self-prepared partially biodegradable hybrid composites comprising an animal-based (human hair) fiber, a plant-based (Luffa cylindrica) fiber, and incense stick ash (ISA) filler have been first time investigated. These composites were fabricated in-house using an Ultrasonicator-assisted hand lay-up technique, incorporating epoxy resin as the matrix and varying ISA filler weight ratios from 0 to 20 wt.% in steps of 5 wt.%. Firstly, the density, and elastic properties through the non-destructive Impulse Excitation Technique (IET), micro-hardness, strengths under tensile, bending, and impact loading are obtained and the surface morphology of fractured surfaces is studied. Subsequently, finite element (FE) analysis using a simulation model in ANSYS is employed to acquire the tensile and flexural strength. Then, a higher-order nonlinear FE model was developed to compute static responses under various loads (point load, sinusoidal line load, uniform line load, uniform load, and sinusoidal load). The model's validity was confirmed through lab-scale experimentation. The composite with 10 wt.% ISA showed the best overall tensile, bending, and shear properties, while the 20 wt.% ISA composites exhibited the highest flexural strength and micro-hardness. Additionally, composites with 10 wt.% ISA, higher aspect ratio, and lower thickness ratio demonstrated significant resistance to deflection under static loading.