Variation of Elastic Moduli with Strain in Carbon/Epoxy Laminates

Abstract

The strain dependence of tensile and compressive elastic moduli in carbon fibre/epoxy resin unidirectional and multidirectional composites is presented. Examined composites were made from prepregs supplied by two producers. Values of relative varia tions of modulus with unit strain are given. All of the examined composites, except (±45)_4s show modulus increase with the rise of tensile strain and modulus decrease with increasing compressive strain. Modulus increase and decrease of composites is attributed to the modulus change of carbon fibre, mainly.