Influence of irregular fibre surface and debonding on the elastic properties of jute/epoxy composites: Micromechanics and finite element approaches

This study examines how irregular surfaces and debonding affect jute/epoxy composites. The study used micromechanics and finite element (FE) analysis to investigate properties such as elastic modulus in the longitudinal (E1) and transverse (E2) directions, major (ν12) and minor (ν21) Poisson’s ratios, and interfacial stresses (σ1, σ2, and τ12, τ23, τ13). The FE models were validated using experimental and analytical results, which showed good agreement. Then, the FE model was extended to analyse the influence of different fibre volume fractions (Vf) on jute/epoxy composites with varied irregular surfaces (IRS%) and debonding (DBS%). The interfacial stress was compared across these variables. DBS% caused significant variation in E2 and σ2, while IRS% led to out-of-shear stresses that crossed the threshold. An increase in IRS% and DBS% at a constant fibre volume fraction did not significantly affect E1. However, increasing Vf from 10–70% increased E1 by 168%. E2, on the other hand, decreased with Vf by 63–68%. Both IRS% and DBS% had a significant influence on interfacial stresses.