Numerical and Analytical Modeling of Aligned Short Fiber Composites including Imperfect Interfaces

This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/composites-part-a-applied-science-and-manufacturing/Access to this item has been restricted by repository administrators at the request of the publisher until June 08, 2017.Finite element calculations were used to bound the modulus of aligned, short-fiber composites with\ud randomly arranged fibers, including high fiber to matrix modulus ratios and high fiber aspect ratios. The\ud bounds were narrow for low modulus ratio, but far apart for high ratio. These numerical experiments\ud were used to evaluate prior numerical and analytical methods for modeling short-fiber composites.\ud Prior numerical methods based on periodic boundary conditions were revealed as acceptable for low\ud modulus ratio, but degenerate to lower bound modulus at high ratio. Numerical experiments were also\ud compared to an Eshelby analysis and to an new, enhanced shear lag model. Both models could predict\ud modulus for low modulus ratio, but also degenerated to lower bound modulus at high ratio. The new\ud shear lag model accounts for stress transfer on fiber ends and includes imperfect interface effects; it\ud was confirmed as accurate by comparison to finite element calculations