The agro-waste materials, such as cow bone and cassava cortex, can be effectively used as reinforcing agents in bio-composite materials, offering both mechanical performance and sustainability benefits suitable for automotive applications.

🔹 Mechanical Performance:

• The incorporation of cow bone and cassava cortex significantly increased the tensile strength of epoxy composites compared to unreinforced samples.
• The optimal hybrid composition (20% cow bone and 20% cassava cortex, 4% NaOH treatment, 100 µm particle size) achieved a tensile strength of 91.80 MPa—a considerable improvement from the base epoxy (72.66 MPa).
• This strength is within the range required for non-load-bearing and semi-structural automotive components, such as interior panels, dashboards, and door trims.

🔹 Material Compatibility and Processing:

• Both cow bone and cassava cortex were locally sourced, processed (cleaned, dried, pulverised), and easily integrated into an epoxy matrix using conventional fabrication techniques (hand lay-up).
• Alkali treatment (NaOH) improved the interface bonding by removing lignin and impurities from the particles, allowing better stress transfer between filler and matrix.
• The composites were shaped and tested using ASTM D638 standards, confirming the viability of these agro-wastes in standard engineering practice.

🔹 Environmental and Economic Impact:

• Using agricultural and animal waste not only reduces the environmental burden of disposal but also adds value to otherwise discarded materials.
• The hybrid composite approach contributes to the circular economy by transforming local waste into functional engineering materials, reducing reliance on synthetic reinforcements such as glass or carbon fibres.
• These bio-fillers are biodegradable, low-cost, and abundantly available, making them ideal for applications in resource-constrained or environmentally conscious manufacturing settings.

✅ Conclusion:

Cow bone and cassava cortex are effective, eco-friendly, and low-cost reinforcement materials for producing high-performance bio-composites. When properly processed and optimised, these agro-wastes can be used in the development of sustainable materials for automotive and other industrial applications. Their use offers a promising path toward reducing material costs, lowering environmental impact, and promoting green engineering practices.