Investigation into mechanical, absorption and swelling behaviour of hemp/sisal fibre reinforced bioepoxy hybrid composites: Effects of stacking sequences

This work focuses on the fabrication of hybrid bio-composites using green epoxy as the matrix material, hemp (H) and sisal (S) fibre mats as the reinforcements. The hybrid composite with sisal/hemp fibres were fabricated by cost effective hand lay-up technique, followed by hot press with different stacking sequences. Static properties of the composites such as tensile, compressive, inter-laminar shear strengths (ILSS) and hardness were examined. The physical properties such as density, void content, water absorption and thickness swelling were also analyzed. The experimental results indicate that hybrid composites exhibited minor variation in tensile strength when the stacking sequence was altered. The hybrid composite with the intercalated arrangement (HSHS) exhibited the highest tensile modulus when compared with the other hybrid counterparts. Hybrid composites (SHHS and HSSH) offered 40% higher values of compressive strength than the other layering arrangements. HHHH sample exhibited the highest ILSS value of 4.08 MPa. Typical failure characteristics of the short beam test such as inter-laminar shear cracks in the transverse direction, micro-buckling and fibre rupture were also observed. •Hybrid biocomposites with varying the stacking sequences of hemp and sisal fibre mats in green epoxy matrix was fabricated.•Effect of varying sequences on the tensile, compression and inter-laminar shear strengths were investigated.•Significant improvements were seen on the tensile and compressive modulus of the composites when compared with the matrix.•Statistical analysis was performed by One-way ANOVA method.