The relation of porosity and creep behavior of glass fiber/epoxy composite: Design of experiments approach

This work aimed to analyze the influence of voids content, morphology (size and shape), and position on the creep behavior of glass/epoxy composites with a reduced number of experiments, applying the design of experiments statistical approach to describe the creep behavior. For this purpose, a three-dimensional microstructure of the materials is created from the images of X-ray microtomography. Analysis of variance shows that the temperature contributes 90% to the initial and final creep deformation; meanwhile, stress and porosity act as secondary factors. Void content is responsible for 15% of the composite creep behavior; meantime, the increase of elliptical and irregular porosity decreases creep resistance. The Weibull analytical model combined with surface response methodology (Taguchi approach) proves to be feasible to predict the creep deformation curve with low error.