Numerical Estimation of Effective Elastic Moduli of Syntactic Foams Reinforced by Short Glass Fibers

Abstract

The mechanical properties of hollow glass microsphere/epoxy resin syntactic foams reinforced by short glass fibers are studied using representative volume elements. Both the glass fibers and the hollow glass microspheres exhibit random arrangement in the epoxy resin. The volume fraction and wall thickness of hollow glass microspheres and the volume fraction of glass fibers are considered as parameters. It is observed that the elastic modulus values of syntactic foams decrease with the increase of microsphere volume fraction when the microsphere relative wall thickness is lower. However, it increases with the increase of microsphere volume fraction when the relative wall thickness exceeds a critical value. The elastic modulus value goes through a maximum when the relative wall thickness is around 0.06 at 25 % volume fraction of microspheres. The addition of glass fibers reduces the critical wall thickness values of the microspheres and increases the mechanical properties of the composites. The highest stress lies on the equatorial plane perpendicular to the loading direction. Adding fibers reduces the large stress distribution areas on the microspheres, and the fibers aligned with the loading direction play an important load-bearing role.

Particle reinforced thermoplastic foams under quasi-static compression

“…To predict the mechanical properties of particle reinforced foams, numerical models have been created through randomly inserting spherical particles (particle reinforcement) into homogeneous host matrix (foams) without detailed modelling of the porous structures of foams (Yu et al, 2016;Chawla and Chawla, 2006;Brown et al, 2011;Cho et al, 2017). Brown et al (2011) created a two-dimensional (2D) finite element (FE) model to study the shock wave propagation of cellular glass particle reinforced foam under dynamic compression.…”