Time-and temperature-dependent compressive behavior of woven carbon fabric reinforced polyamide composite laminate

Abstract

Plain woven carbon fabric reinforced polyamide (CF/PA) composite laminate was developed using hot-pressed processing with a vacuum-assisted system. Temperature-dependent mechanical properties of the CF/PA composite laminate under longitudinal compressive loading were examined. The compressive mechanical properties of the composite laminate decreased considerably with increasing the temperature to 120°C. The compressive strength and strain at maximal stress reduced rapidly below 80°C, while the compressive modulus declined slightly underneath 50°C. The glass transition temperature of the CF/PA composite was found to be about 50°C by the differential scanning calorimetry, which almost corresponded to the slight reduction of the elastic modulus at temperatures below 50°C. The time-dependent creep behavior of the CF/PA laminate under compressive loading at isotherms between 25°C and 50°C was studied. Creep strains of the CF/PA composite samples increased with rising temperature. The smooth creep compliance master curve of the CF/PA composite was obtained by shifting short-term creep compliance curves using the time–temperature superposition principle. The master curve provided a creep prediction to 961.6 days with the measured data in only 12.5 days.