Numerical investigation of the stress field of particulate reinforced polymeric composites subjected to tension

Abstract

SUMMARYThe aim of the present study is the detailed numerical investigation of the stress/strain distribution in polymeric matrix composites reinforced with spherical inclusions, using the finite element method (FEM). Perfect adhesion between the matrix and the inclusions was assumed and from the computed stress/strain profiles of the system, debonding initiation and propagation can easily be predicted. Analytical models available in the literature may predict the stress/strain distribution within the inclusion and along the matrix/inclusion interface, while the FEM may yield results for the whole composite, including within the inclusions. Three typical volume fractions of the composite were examined and the results were justified by the analytical predictions of other researchers. The numerical results show that the matrix starts to debond from the inclusions at angular distance forty-five degrees and as the applied load increases the debonding zone gradually extends.

Multiaxial yield behaviour of polypropylene

“…On a local scale, complex compressive stresses also play a major role in joint technologies (e.g., screw joints, clamping, fastening), in cutting processes and in tribological applications (i.e., friction, wear and scratch processes) also including fretting fatigue loads [1][2][3][4]. Another example for the development of multiaxial local stresses is in the area of polymer matrix composites, in which a multiaxial stress field develops on a local scale around the reinforcing phase, even though the external load applied to the material may be a uniaxial tensile load [5] Considering that the behavior of polymeric materials under tension and compression may differ particularly in the yield and post-yield regime [6][7][8], the need to characterize the whole range of stress states of plastics becomes evident. Moreover, the above examples indicate the importance of a e-mail : michael.jerabek@borealisgroup.com adequate test set-ups in a comprehensive manner and underline the need for appropriate test methodologies.…”

Effect of elastic or shape memory alloy particles on the properties of fiber-reinforced composites

“…The pioneering study of Eshelby [1957] provided expressions for the stresses just outside a spheroidal inclusion. This work was further continued by Tandon and Weng [1986] and Kakavas and Kontoni [2005] who also illustrated that the analytical results were in a good agreement with the finite element analysis. Micromechanical strength conditions can be determined by specifying the stress in the matrix, at the particle-matrix interface, and in the particles, and subsequently applying strength criteria to the matrix and particles and at the interface.…”

Two-dimensional polynomial eigenstrain formulation of boundary integral equation with numerical verification

“…In particular, the determination of elastic states of an embedded inclusion is of considerable importance in a wide variety of physical and engineering applications. By Eshelby's idea of eigenstrain solutions and equivalent inclusion, a diverse set of research has been reported analytically [3][4][5][6][7] and numerically [8][9][10][11][12][13][14][15][16] . It should be mentioned that the eigenstrain solution can represent various physical problems, where the eigenstrains can correspond to the thermal-mismatch strains, the strains due to the phase transformation, the plastic strains, as well as the intrinsic strains in the residual stress problems [17] .…”

“…Numerical simulations using the finite element methods (FEM) [10] , the volume integral methods (VIM) [11][12][13] , or the boundary element methods (BEM) [19] have been conducted for the analysis of engineering problems with the inhomogeneities of various shapes and material properties. The solution scale of the FEM is usually very large since both the matrix and the inhomogeneity should be discretized over their entire solution domains.…”