Based on the experimental measurements of materials dielectric strength, this paper is focused on the relationships between dielectric strength of the materials and tensile stress applied on them. The experimental results indicated that the dielectric strengths of the unsaturated polyester resin and the unidirectional glass fiber reinforced composites had an obvious decrease compared with the samples without of it. Furthermore, the dielectric strength decreased with the increase of tensile stress. When tensile stress reached 50% of the material tensile strength, the dielectric strength of the resin decreased 13.36%, and the unidirectional glass fiber reinforced unsaturated polyester composites decreased 19.86% with the tensile stress in the longitudinal direction and 12.06% in the transverse direction. When the experimental samples were broken down by electricity, cracks and pores which would lead to stress concentration were created between the electrodes around the breaking-down point. In a word, it is vital to make a research about the effect of stress on the insulating properties of materials.
Manufacturing of unidirectional glass-fiber-reinforced composites via frontal polymerization: A numerical study
