A physically-based constitutive model for the shear-dominated response and strain rate effect of carbon fibre reinforced composites

Abstract

A significant hardening response is often observed for the shear-dominated deformation of Carbon Fibre Reinforced Plastics (CFRP). This non-linear response is typically modelled by fitting a strain hardening law against experimental stress-strain curves. Inspired by crystal plasticity framework, we develop a micro-mechanically motivated constitutive model to capture the matrix shearing and fibre rotation of CFRP under finite strain deformation and different strain rates. Strain rate dependency of the shear modulus and yield strength of the matrix was modelled through scaling functions. This physically-based constitutive model is first verified by simple shear and transverse compression tests, followed by comprehensive validations against the measured stress-strain responses of unidirectional (UD) and cross-ply composite laminates subjected to quasi-static and dynamic off-axis loading. The finite element predictions and analytical models of CFRP lamina under simple shear loading confirms that the initial yielding is governed by the shear yield strength of matrix, while the hardening behaviour is dependent on the modulus and rotation of carbon fibres. This model accurately predicts the non-linear behaviour of CFRP under off-axis loading at different strain rates, without the need of a curvefitted strain hardening law.

Phase field fracture predictions of microscopic bridging behaviour of composite materials

“…Several numerical methods are being used in these computational micromechanics endeavours, including Continuum Damage Mechanics (CDM) models [15][16][17][18], the Extended Finite Element Method (X-FEM) [19,20], Cohesive Zone Models (CZM) [21] and the Floating Node Method [22]. Despite their effectiveness, these techniques are often limited in capturing complicated crack paths, which naturally result from crack coalescence, branching and bridging events.…”

Tension, compression, and shear behavior of advanced sheet molding compound (A-SMC): Multi-scale damage analysis and strain rate effect

“…Modeling of the global mechanical and damage behavior of composites is necessary in design calculation of structural components [29,30]. One can note that debonding at fiber/matrix interfaces is the main damage mechanism of SMC composites [31,32].…”

Failure analysis of glass fiber and basalt fiber reinforced polymer composites under an extreme environment with high‐temperature, high‐pressure and H2S/CO2 exposure

“…Over the years, numerous composite material failure models have been proposed to quantify and predict the effects of various post-processing behaviors on the properties of fiber reinforced composite materials. 18,19 However, there is still significant uncertainty and debate about accurately predicting the failure of composite materials. Criteria that do not incorporate the physics of composite materials, like the Von-Mises stress theory of isotropic materials, are typically represented by a single polynomial and cannot predict local failure under complex stress states.…”

“…Over the years, numerous composite material failure models have been proposed to quantify and predict the effects of various post‐processing behaviors on the properties of fiber reinforced composite materials 18,19 . However, there is still significant uncertainty and debate about accurately predicting the failure of composite materials.…”