Effect of nano silica on mechanical and water absorption properties of basalt/polyester hybrid composite with glass/hemp

In this paper, Unsaturated Polyester Resin (UPR) composites with an optimum weight percentage of Basalt fibre(BF), Glass Fibre (GF), Hemp fibre (HF) and hybridization of Basalt with Glass (BG) and with Hemp (BH) and with a varying weight percentage of Nano Silica (0,1,2,3,4,5) were developed using VARI technique. The effects of different fibres, hybridization and percentage of Nano Silica in Mechanical Properties (Tensile, Flexural, Izod Impact and Hardness) and Water absorption characteristics of composites were investigated and discussed. The maximum tensile strength and Tensile Modulus were found for UPR + BF + 2% Nano Silica (316.5 MPa & 11.29 GPa, respectively). The hybrid composites showed intermediate results between the neat fibres composites. It was found that all the mechanical properties were enhanced till 2% Nano Silica loading, and after that, the values started declining. Water absorption behavior was studied till the water uptake percentage attained a constant value, and it was found that equilibrium water uptake decreased till 3% of Nano Silica loading. The fractured surface of the composites was studied for fibre pull out, fibre breakage, interface and uniformity using Scanning Electron Microscopy (SEM).