Sustainable innovations: Mechanical and thermal stability in palm fiber-reinforced boron carbide epoxy composites

• Enhanced tensile strength: 15 % increase to 95 MPa with boron carbide-reinforced PFF composite. • Improved flexural strength: achieved 18 % higher flexural strength at 140 MPa. • Superior impact resistance: 20 % better impact strength at 25 J. • Reduced water absorption: 30 % decrease in water absorption to 1.2 %. • Increased thermal stability: retained 45 % of weight at 350 °C, boosting high-temperature performance. This study reports the development of a sustainable composite material by integrating boron carbide (B4C) nanoparticles into palm fruit fiber (PFF)-reinforced epoxy matrices. The mechanical and thermal properties of these composites were thoroughly assessed, yielding promising results across key performance metrics. Tensile strength increased to 41.73 MPa with 4 % B4C, while flexural strength reached 43.29 MPa at the same concentration. Impact energy also saw an improvement, peaking at 5.6 kJ/m² with 4 % B4C. Similarly, hardness values showed an upward trend, with a Shore D value of 73. Additionally, water absorption was reduced from 7.2 % to 5.3 %, indicating enhanced moisture resistance. Thermal analysis confirmed the superior thermal stability of the composite, as shown by Thermogravimetric Analysis (TGA) and Differential Thermogravimetry (DTG) curves, with the maximum mass loss occurring at a higher temperature for the 4 % B4C composite. Fatigue stress testing also demonstrated improved durability, with the 4 % and 5 % composites exhibiting higher fatigue resistance over multiple cycles. The findings suggest that a 4 % concentration of boron carbide achieves an optimal balance of improved mechanical strength, durability, and thermal stability, making these composites suitable for high-performance applications while promoting environmental sustainability.