Influence of silica fillers on failure modes of glass/vinyl ester composites under different mechanical loadings

Abstract

Glass/vinyl ester composites are widely used to produce vessels and structures for applications in marine environment. Matrix cracking, delamination and fibre breakage are major modes of failure in these composites. This paper focusses to enhance the performance of glass/vinyl ester composites by the addition of silica microparticles. The particle loading helped to enhance the mechanical performance of matrix by reducing the chances of matrix cracking and delamination, due to better particle/matrix interfacial adhesion. Composite materials were fabricated without particles and with 2% and 5% particle loading (by weight of resin), using UD glass fabric reinforcement. The mechanical performance was investigated in terms of tensile strength, flexural strength, short beam shear, impact resistance and barcol hardness. The results show an increase in the properties of composites by the addition of silica microparticles. The investigations of the failure mode revealed that composites without any particles have exhibited matrix cracking, delamination and reinforcement failure in tensile and flexural mode. But the particle loaded composites exhibited only matrix cracking and reinforcement failure, indicating a substantial increase in the matrix strength and interfacial adhesion. Similarly, in case of drop weight impact, a high energy was absorbed by the particle loaded composite as compared to the one without particles. The barcol hardness of composite was also found to increase with particle loading.