TY - JOUR
T1 - A micromechanical model to study failure of polymer-glass syntactic foams at high strain rates
AU - Shams, Adel
AU - Panteghini, Andrea
AU - Bardella, Lorenzo
AU - Porfiri, Maurizio
N1 - Funding Information:
This work has been supported by the Office of Naval Research Grant N00014-10-1-0988 with Dr. Y.D.S. Rajapakse as the program manager. Views expressed herein are those of the authors and not of the funding agencies. The authors are grateful to Mr. G. Perini for his help with the finite element model.
Publisher Copyright:
© 2017 Elsevier B.V.
PY - 2017/7/1
Y1 - 2017/7/1
N2 - Syntactic foams are lightweight composite materials that find extensive application as core materials for sandwich panels in marine and aerospace structures. While several models have been proposed to analyze the elastic response and failure of these composites at small strain rates, the understanding of syntactic foam behavior at high strain rates remains elusive. In this work, we simulate the response of polymer-glass syntactic foams under high strain rate compressive loading conditions, by using a three-dimensional micromechanical model consisting of fifty hollow spheres randomly dispersed in the matrix material. The mechanical response of the matrix is described by generalizing a phenomenological viscoplastic constitutive model from the literature to the three-dimensional stress state. The filler behavior is assumed to be linear elastic until brittle failure, which is predicted on the basis of a structural criterion for glass microballoons. The collapse of the first glass microballoon is hypothesized to trigger the failure of the whole composite. Such a micromechanical model is implemented in the commercial finite element code ABAQUS. We focus on glass-vinyl ester syntactic foams and perform a parametric study to elucidate the roles of strain rate, microoballoon density, and microballoon volume fraction on the compressive modulus, strain energy, and effective strength. Comparisons between model findings and available experimental data are presented to assess the accuracy of the proposed numerical model. Our results enable the study of syntactic foam behavior at high strain rates, for a wide range of strain rates, microballoon densities, and microballoon volume fractions. This knowledge is expected to aid in the design of lightweight composite materials subjected to high strain rate compressive loading.
AB - Syntactic foams are lightweight composite materials that find extensive application as core materials for sandwich panels in marine and aerospace structures. While several models have been proposed to analyze the elastic response and failure of these composites at small strain rates, the understanding of syntactic foam behavior at high strain rates remains elusive. In this work, we simulate the response of polymer-glass syntactic foams under high strain rate compressive loading conditions, by using a three-dimensional micromechanical model consisting of fifty hollow spheres randomly dispersed in the matrix material. The mechanical response of the matrix is described by generalizing a phenomenological viscoplastic constitutive model from the literature to the three-dimensional stress state. The filler behavior is assumed to be linear elastic until brittle failure, which is predicted on the basis of a structural criterion for glass microballoons. The collapse of the first glass microballoon is hypothesized to trigger the failure of the whole composite. Such a micromechanical model is implemented in the commercial finite element code ABAQUS. We focus on glass-vinyl ester syntactic foams and perform a parametric study to elucidate the roles of strain rate, microoballoon density, and microballoon volume fraction on the compressive modulus, strain energy, and effective strength. Comparisons between model findings and available experimental data are presented to assess the accuracy of the proposed numerical model. Our results enable the study of syntactic foam behavior at high strain rates, for a wide range of strain rates, microballoon densities, and microballoon volume fractions. This knowledge is expected to aid in the design of lightweight composite materials subjected to high strain rate compressive loading.
KW - Effective strength
KW - Finite element model
KW - High strain rates
KW - Inelastic deformation
KW - Micromechanical model
KW - Syntactic foam
UR - http://www.scopus.com/inward/record.url?scp=85019034644&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85019034644&partnerID=8YFLogxK
U2 - 10.1016/j.commatsci.2017.04.007
DO - 10.1016/j.commatsci.2017.04.007
M3 - Article
AN - SCOPUS:85019034644
SN - 0927-0256
VL - 135
SP - 189
EP - 204
JO - Computational Materials Science
JF - Computational Materials Science
ER -