Multiscale Prediction of Equivalent Elastic Properties of Carbon/Glass Hybrid Composite Laminates

A multi-scale framework is proposed for predicting the equivalent engineering elastic constants of carbon/glass hybrid composite laminates with different fiber volume fractions V_f by integrating multiscale finite element homogenization with analytical micromechanics. Biaxial carbon fiber fabric reinforced vinyl ester composites are used as the target material system, and representative volume element (RVE) models are constructed sequentially at the lamina, laminate, and hybrid-laminate scales. At the lamina scale, the analytical self-consistent field micromechanics (SCFM) approach and the RVE method give highly consistent predictions for the fiber-dominated longitudinal modulus E₁ and in-plane shear modulus G₁₂, with deviations below 2%. However, the SCFM approach overestimates the transverse modulus E₂ and transverse Poisson's ratio ν₂₃ as the V_f rises. The unidirectional lamina constants predicted by SCFM and RVE are then used as inputs for an analytical solution for predicting elastic constants (ASPE) and a finite-element-analysis-based micromechanics (FEAM) model of laminate and hybrid-laminate. At the laminate scale, the moduli predicted by ASPE(SCFM) and ASPE(RVE) differ by less than 2%, whereas the out-of-plane properties are sensitive to the transverse lamina inputs. Experimental validation shows that the E_x values predicted by ASPE(RVE) and FEAM(RVE) deviate from the measured average by approximately 3.5%, with good agreement also obtained for G_xy and ν_xy. At the hybrid-laminate scale, ASPE(RVE) and FEAM(RVE) exhibit only minor differences in estimating the in-plane moduli, out-of-plane moduli, and Poisson's ratios.