Coupling effect of strain rate and temperature on tensile damage mechanism of polyphenylene sulfide reinforced by glass fiber (PPS/GF30)

Abstract

Influence of loading temperature on the damage mechanism of polyphenylene sulfide (PPS) reinforced by glass fiber (PPS/GF30) under tension was experimentally studied from quasi-static (QS) to high strain rates. Two kinds of PPS/GF30 samples were prepared: PPS-0° and PPS-90° (correspond to fibers oriented parallel and perpendicular to the injection direction, respectively). After microscopic observation and thermomechanical characterizations by dynamic mechanical analysis, tensile tests up to failure with strain rates varying from 10−3 s−1 to 100 s−1 have been carried out at 25°C and 120°C with regard to PPS/GF30 glass transition temperature. To achieve the coupling effect of high strain rate and high temperature, a special chamber was designed to install on the servo-hydraulic machine. The results of QS tensile tests confirm the significant effect of fiber orientation and temperature on the Young’s modulus, the ultimate stress, and strain. High strain tensile test results showed that the PPS/GF30 composite is strain rate dependent at both temperatures. The results indicated that Young’s modulus remains constant by strain rate increasing at both temperatures while ultimate stress and strain are increased. No significant damage has been observed at 25°C in QS loading, whereas the macroscopic damage variable is increased to 20% at 120°C. Debonding at the fiber–matrix interface is the main damage mechanism at 120°C.