Impact of Bran Filler Amount on Flax Fiber Reinforced Epoxy Composite - Mechanical and Thermal Properties for Secondary Structural Applications
Thandavamoorthy Raja, D. Yuvarajan, V. Sundaram, Vidhya Lakshmi S, Veeraragavan V.P
Abstract
This study examines the mechanical and thermal properties of flax fibre-reinforced epoxy composites with three different concentrations of bran filler to assess their potential for secondary structural applications. The mechanical parameters, such as tensile strength, flexural modulus, and Izod impact resistance, were investigated systematically, in addition to thermal properties, including thermal conductivity, coefficient of linear thermal expansion, and heat deflection temperature. SEM was used to analyse the fracture surfaces after tensile failure to understand the material’s failure mechanisms. Adding bran filler to flax fiber reinforced epoxy composites had a notable impact on mechanical and thermal properties. Testing showed that the ideal bran filler improved tensile strength and flexural modulus without compromising impact resistance, indicating a synergistic reinforcement effect. Thermal investigation revealed that using bran filler enhanced thermal stability by raising heat deflection temperatures and regulating thermal conductivity and expansion coefficients to meet the demands for thermal resilience in secondary structural applications. Scanning Electron Microscopy (SEM) research revealed how the bran filler altered the fracture behaviour of the composite by enhancing the adhesion between fibres and matrix and improving energy dissipation processes. The results indicate that flax fibre-reinforced epoxy composites, enhanced with bran filler, offer a promising, ecofriendly option for secondary structural uses requiring mechanical strength and heat resistance.