Loading Rate Sensitivity of Glass Fiber-epoxy Composite at Ambient and Sub-ambient Temperatures

Abstract

Little information regarding the effects of weight fraction of constituent phases of freeze-thaw response in polymer composites at different loading rates and temperatures has been published to date. The present experimental study uses 3-point flexural test to qualitatively assess such effects for 55, 60 and 65 weight percentages of E-glass fibers reinforced epoxy composites during cryogenic and after thawing conditions. The specimens were tested at a range of 0.5 mm/min to 500 mm/min crosshead speed to evaluate the sensitivity of mechanical response during loading at ambient and sub-ambient (-80°C temperature). These shear strength values are compared with the testing data of as-cured samples. The findings are explainable at lower range of crosshead speed. The data obtained at higher loading rate suggest further investigation to establish the nature.