Effects of thermal shock fatigue on short glass fiber-reinforced PBT composites embedded by thermally conductive particles

Abstract

This study investigated the effects of thermal shock fatigue loading on the tensile behaviors and thermal conductivity of polybutylene terephthalate (PBT) resin composites embedded with Glass fibers (GF) and thermally conductive Boron nitride (BN) particles. Thermal conductivity increased, but tensile strength decreased when the fraction of BN particles was increased. After thermal shock fatigue loading, the failure strain of unfilled PBT became considerably smaller. Meanwhile, the effective difference of the glass transition temperature did not occur. In the case of filled PBT, fine debonding occurred at the interfaces of GF, although this behavior was not observed at the interfaces of the BN particles. At a fraction of GF 15 wt%, BN contents higher than 20 wt% reduced the elastic modulus but improved tensile strength and thermal conductivity. Thermal shock fatigue loading further increased the strength and thermal conductivity of PBT at high BN fractions.