An Orthotropic Integrated Flow-Stress Model for Process Simulation of Composite Materials—Part II: Three-Phase Systems

Abstract

In this paper, the two-phase orthotropic integrated flow-stress (IFS) process model presented in Part I is extended to a three-phase model where the third-phase accounts for the presence of gas in the composite material system. The gas flow and its compressibility are taken into account, while the seamless transformation of the resin material from its initially liquid stage to a cured solid material is incorporated within the previously developed IFS framework. A three-phase orthotropic flow model is employed to describe the behavior of the composite material during the pregelation stage of the process cycle which transforms continuously to a solid mechanics model using a stepwise three-phase micromechanics. The model is implemented in a u–v–P plane strain finite element code similar to that presented in Part I but with extended degrees-of-freedom accounting for the velocity and pressure of the gas phase. The numerical model is applied to the debulking and curing process of an L-shaped unidirectional composite laminate. Performance of the model is assessed through evaluating the process-induced deformations and residual porosity distribution over the spatial domain of the laminate.

Improving the Mechanical Properties of the Air-Conditioning Pipe Using Composite Materials

“…An L-shaped unidirectional composite laminate's debulking and curing processes are modeled numerically. The residual porosity distribution over the laminate's domain and process-induced deformations are used to evaluate the model's performance [11]. A computational simulation model of the active pulsed thermography technique was used to assess the detection limit of the absence of adhesive flaws in GFRP adhesive composite joints.…”

Physics-integrated Neural Differentiable (PiNDiff) Model for Composites Manufacturing

“…Although computer models have been successfully used to predict various physical processes in many applications (e.g., aerospace [7,8], structure [9], biomechanics [10,11], etc. ), the physics-based computational modeling for composite manufacturing is a less explored area, and there are only very few studies on modeling the impregnation or pyrolysis processes in past decades [12][13][14][15][16][17][18][19]. This is because the manufacturing processes of composites involve many coupled physics and complex mechanisms, both mechanically and chemically, which are far from being fully understood, making traditional first-principles physics-based modeling infeasible.…”

Experimental characterisation of the in-plane shear behaviour of UD thermoset prepregs under processing conditions

“…The examples above highlight the key role played by in-plane shear in the defect formation mechanisms in composite manufacturing. It can also be found in the open literature on thermoforming [3,5,12,13], AFP deposition [7][8][9]11], and autoclave curing processes [14][15][16]. These works indicate the highly temperature and rate dependent nature of prepreg loaded in pure shear, which will manifest itself in the real manufacturing processes and needs to be considered in any virtual platform aiming at simulating them.…”