Synthesis and effect of using silica fume particles on shear properties of basalt fibers‐epoxy composites

In this study, the effect of the addition of silica particles modified with silane agent on the mechanical properties of basalt fibers- composites were studied with the interlayer shear strength (ILSS) test. In the first stage, silica epoxy fume particles were synthesized using the sol-gel method and surface modified using tri mercaptopropyl trimethoxy silane agent. The results of the characterization showed that the synthesized powder is nanometric scale, amorphous and high purity. The surface-modified silica fume particles (0, 2, 4, 6 wt.%) were distributed inside the epoxy matrix using a mechanical stirrer and ultrasonic waves. The hand lay-up method was used to fabricate composite samples, then the effect of adding these particles on the mechanical properties of basalt fibers-epoxy composites under interlayer shear loads was studied. The results of the research indicated that the addition of silica fume particles has a significant effect on improving the mechanical properties of basalt fibers-epoxy composites, and the greatest improvement in mechanical properties was achieved by adding 4 wt.% of modified silica fume particles. In the case of composites without SF particles, the shear strength was 34 MPa, which was increased to 40 MPa by adding 4 wt.% of SF particles (about 20% improvement). On the other hand, results demonstrated that the optimal distribution of silica fume particles within the polymer matrix performs an impressive role in improving the mechanical response of composite samples.