Micro-structure Constitutive Theory And Damage Analysis Of Particulate-reinforced Composites

In this paper, based on micro-mechanics method, a three-phase composite model ispresented for particulate-reinforced composite. It is assumed that the particles wereuniformly distributed in an infinite matrix, and the particle, interphase, and matrix are allinclusions of composites. Constitutive equations are derived for the stress and strain ofeach phase of the composite with multi-inclusions, subjected to a far-field tension. Basedon these constitutive laws, the effective bulk, shear and Young’s modulus are obtained.The dependence of the effective modulus of composites on particle volume fraction,interfacial strength, interphase properties and multi-particles is discussed.A statistical debonding criterion is adopted to characterize the quantities of debondedparticles. The debonded particles are regarded as voids with the same volume fraction. Adamage model is subsequently considered in accordance with the Weibull function tocharacterize the evolution of interfacial debonding between the particle and the interphase.The influence of progressively damage on the effective modulus is also discussed.In order to characterize the elasto-plastic behavior of particle composites, Ludwik’sequation was adopted to describe the effective stress-strain relation of the matrix.Moreover, the statistical stress-strain relations of progressively debonded composites aregraphically predicted and discussed. The influence of debonding damage, particle volumefraction, interphase properties and bonding strength on overall mechanical behavior ofcomposites is discussed.Numerical analyses were carried out on a series of particle-reinforced composite for theeffective properties based on the present model. Furthermore, the initial particles arereplaced by voids and effective modulus of porous material was obtained. Then, theinfluence of volume fraction of voids on the effective properties is discussed. Thecomparison between the present method and other methods is discussed, and it is shownthat the predictions are agreeable with the experimental results.