The mechanical properties of epoxy composites reinforced with varying compositions of carbon fiber, carbon powder, and boron nitride (BN) additives. The relationship between the weight percentage of carbon fiber, the size of carbon powder, and the inclusion of BN was explored through measurements of Young’s Modulus, Ultimate Tensile Strength (UTS), and Impact Strength. The results indicate a positive correlation between the carbon fiber content and both stiffness and tensile strength. Specifically, composites with higher carbon fiber content (6 wt%) exhibited significantly improved Young’s Modulus and UTS compared to those with lower fiber content (2 wt%). Carbon powder size also influenced mechanical properties, with finer powders improving rigidity, while larger particles contributed to increased tensile strength under certain conditions. The addition of BN was found to significantly enhance impact strength, particularly at higher concentrations (6.5 wt%), attributed to its lubricating properties that improve energy absorption during impact. Sample 6, which incorporated 6 wt% carbon fiber, 150 µm carbon powder, and 3.9 wt% BN, achieved optimal mechanical performance with high UTS (26.08 MPa) and superior impact strength (85.47 J/m²). The complex interactions between these components highlight the importance of composite design in optimizing material performance for specific applications. This study provides valuable insights into the development of advanced composites, particularly for applications requiring a balance of high tensile strength, stiffness, and impact resistance.

Keywords: Surface coating, Carbon fibre, Sporting goods, Tensile properties.