Mechanics of hybrid polymer composites: analytical and computational study

Abstract

Three different models with increased complexity to study the effects of hybridization on the tensile failure of hybrid composites are proposed. The first model is a model for dry bundles of fibres based on the statistics of fibre strength. The second is a model for composite materials based on the multiple fragmentation phenomenon. Lastly, a micromechanical numerical model is developed that considers a random distribution of fibres and takes into account the stochastic nature of fibre strength. This study aims to understand the controlling factors that lead to pseudo-ductility, as well as establish the sequence of failure mechanisms in hybrid composites under tensile loadings.

A computationally-efficient hierarchical scaling law to predict damage accumulation in composite fibre-bundles

“…Other Monte-Carlo simulations have considered other matrix and/or interface responses, e.g. with viscoelasticity [27], strainhardening [23,24,29], transverse matrix cracks [29], progressive decohesion [29], or with a given debond length [27]. However, the impact of considering more complex matrix/interface constitutive laws on the predicted strength and ibre-damage accumulation in composites is still to be quanti ied;…”

“…These models aim to represent stress ields near single ibre-breaks accurately, although most assume regular packing [5, 17-25, 27, 30]; many models [16,18,25,26] also neglect the increase in the stress-recovery length near broken clusters, which was shown to overestimate bundle strength [30]; moreover, all models [5,[16][17][18][19][20][21][22][23][24][25][26][27]30] consider simpli ied matrix constitutive laws (e.g. neglecting progressive matrix fracture), neglect dynamic stress concentrations, and assume perfectly-aligned ibres (the only exceptions [28,29] considered very small representative volume elements). In addition, simulation results are often not compared against experiments [16-20, 26, 28, 29], and when compared they tend to overpredict the average strength of composites [5,21,22,24,25]; they also signi icantly underpredict the variability of strength distributions [25], and underpredict (or fail to predict) M A N U S C R I P T A C C E P T E D ACCEPTED MANUSCRIPT size-effects for increasing ilament counts in bundles [22,26].…”

“…More recently, the increase in computational power enabled several researchers to propose Monte-Carlo simulations for the tensile failure process in UD-FRPs [5,[16][17][18][19][20][21][22][23][24][25][26][27][28][29][30]. These models aim to represent stress ields near single ibre-breaks accurately, although most assume regular packing [5, 17-25, 27, 30]; many models [16,18,25,26] also neglect the increase in the stress-recovery length near broken clusters, which was shown to overestimate bundle strength [30]; moreover, all models [5,[16][17][18][19][20][21][22][23][24][25][26][27]30] consider simpli ied matrix constitutive laws (e.g.…”

Simulation of the Mechanical Response of Thin-Ply Composites: From Computational Micro-Mechanics to Structural Analysis

“…Carbon fibre-reinforced polymers (CFRPs) are characterised by high specific properties (strength-to-weight and stiffness-to-weight ratios), high fatigue resistance, high corrosion resistance, and good thermal stability, making them well suited for advanced structures especially when weight is an important variable in the design process. However, in spite of the improved specific properties of CFRPs and recent technological developments [1,15,60,66,82,109,127,129,166], their heterogeneity at the ply-scale still poses some limitations on the mechanical performance. In fact, the damage behaviour of CFRPs can be quite different from that of commonly used materials such as metals, generally more complicated, and dependent on several factors, such as the properties of the constituent materials, the fibre orientation, the stacking sequence, or the nature of loading, to mention just a few.…”

Multiscale approach for identification of transverse isotropic carbon fibre properties and prediction of woven elastic properties using ultrasonic identification

“…Popular reference works are [4,21]. Examples of where these are referenced include but are not limited to [2,7,22,23,24,25]. Another approach is to reverse engineer the constituent properties from macro-scale experimental results.…”