A physically-based constitutive model for the shear-dominated response and strain rate effect of carbon fibre reinforced composites. (15th July 2020)

• Record Type: Journal Article
• Authors: Tan, Wei; Liu, Burigede
• Is Part Of: Composites. Number 193(2020)
• Publication Date: 2020-07-15
• Subjects: Polymer-matrix composites (PMCs) -- Plastic deformation -- Micro-mechanics -- Computational modelling; Composite materials -- Periodicals; Materials science -- Periodicals; Composite materials; Periodicals; Electronic journals; 620.118
• DOI: 10.1016/j.compositesb.2020.108032
• Languages: English
• ISSNs: 1359-8368

Abstract

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 curve-fitted strain hardening law. Graphical abstract: Image 1