Effect of Thermal Aging on Mechanical Performance of GF/PBT Composites for High Voltage Bushing

The present work aims to study the mechanical performance of glass fiber reinforced polybutylene terephthalate (GF/PBT) composite materials used for high-pressure casing under different thermal aging temperatures. Both tensile and three-point bending tests are conducted on the thermally aged GF/PBT samples. Meanwhile, the stress analysis is performed using the finite element method, and the tensile fracture morphology and mode are observed using a scanning electron microscope. The findings reveal a decline in both tensile and bending strengths of GF/PBT as the aging temperature rises. It is worth noting that the elastic modulus of the composite samples remained relatively unaffected by thermal aging. The thermally aged materials exhibit brittle fracture, which directly affects the bonding performance between glass fibers and PBT matrix.