TWO-PHASE CONSTITUTIVE MODELFOR THE ANALYSIS OF NONLINEARDEFORMATION OF WOVEN POLYMERMATRIX COMPOSITE

Key findings from this study

This research indicates that:

• the constitutive model predicts composite strength with maximum 15% error for lay-ups with limited matrix nonlinearity
• the model accurately captures stress-strain response through 5% axial strain in highly nonlinear lay-ups
• the approach accounts for coupled effects of plastic matrix deformation, microdamage, and yarn rotation in fabric composites

Overview

A two-phase constitutive model for describing nonlinear deformation of woven polymer matrix composites was developed and validated. The model extends prior multiphase approaches to capture irreversible plastic deformations in the polymer matrix, distributed microdamage, and fabric yarn rotation during finite element analysis.

Methods and approach

The model was implemented within the UPF module of ANSYS Mechanical. Standard tensile and shear tests characterized material behavior. Single-element simulations of elementary loading cases provided parameter calibration. Validation used static tests on fabric carbon fiber-reinforced plastic specimens with symmetric lay-ups and off-axis specimens cut at varying angles to the warp direction.

Results

The model predicted composite strength under plane stress with maximum error of 15% for lay-ups exhibiting limited matrix nonlinearity (0°, ±15°, and ±30°). For lay-ups with pronounced deformation nonlinearity (30° and 45°), the model accurately captured stress-strain behavior through 5% axial strain. The approach successfully describes loading processes across the tested material configurations.

Implications

The validated model enables more accurate finite element prediction of woven composite behavior during nonlinear deformation regimes. This capability supports engineering applications requiring assessment of composite strength and deformation response under complex loading states, particularly for structures experiencing moderate to large strains. The 15% prediction error for linear-dominated lay-ups and accurate tracking of stress-strain behavior through intermediate strains provides quantified confidence bounds for structural design applications.

Scope and limitations

This summary is based on the study abstract and available metadata. It does not include a full analysis of the complete paper, supplementary materials, or underlying datasets unless explicitly stated. Findings should be interpreted in the context of the original publication.