Three Dimensional Effective Properties of Composite Materials for Finite Element Applications

Abstract

A model has been developed to compute the effective properties for an arbitrarily shaped element with multiple anisotropic material regions. The analysis utilizes a finite element technique to resolve the complexity of three-dimensional layer geometry, anisotropy, ply orientations, and multi-material regions within an element. Accordingly, the model accounts for complex geometries requiring changes in mesh density and/or arbitrarily shaped elements that cannot be readily aligned with the layers of the laminate. Discontinuity due to ply drop-off or layer terminations within an element is also considered. The computed elastic constants are accurate, especially for the transverse shear properties. The analysis is particularly suitable for finite element applications of near-net shaped thick-section structures. A preprocessor was developed incorporating the effective property model to allow for generation of finite element representations for computer codes such as DYNA3D and ABAQUS.

Dynamic Response and Fracture of Composite Gun Tubes

“…Accordingly, a smeared properties for the composite laminate is used. These properties, which are representative of the unique layup construction of the tube, were calculated using a model developed by Alexander and Tzeng [12]. The smeared property approach allows a single finite element to contain several layers and reduces the size of the finite element model.…”

Elasto-Plastic Stress Analysis of Thermoplastic Matrix Composite Laminated Plates Under In-Plane Loading

“…The solution of laminated plate elements includes transverse shear deformations. Therefore, the stress-strain relation for an orthotropic layer in any orientation angle in the plane of the layer is given as (1) where the transformed reduced stiffnesses Q ij are given in terms of the orientation angle and the engineering constants of the material.…”

“…Composite materials offer great potential and flexibility in structural design because of the anisotropy of material properties, unique ply-by-ply constructions, and novel fabrication methods (Alexander and Tzeng, 1997). For applications in advanced composite systems made up of polymericmatrix materials and high strength and stiffness reinforcements such as carbon fibers, thermosetting polymers have been utilized almost exclusively for several decades.…”

“…C OMPOSITE MATERIALS OFFER great potential and flexibility in structural design because of the anisotropy of material properties, unique ply-by-ply constructions, and novel fabrication methods [1]. Although thermosetting polymers have been utilized almost exclusively for several decades, the introduction and development of new thermoplastics, e.g., Torlon, PEEK and Ryton, followed by numerous other candidates, as matrix materials in structural composites have given another dimension to the application of reinforced plastic materials [2].…”

Finite element and micromechanical modeling for investigating effective material properties of polymer–matrix nanocomposites with microfiber, reinforced by CNT arrays

“…RVE can show the real stress and strain of a material and offers a good understanding of its elastic properties. Considerable efforts have been made to determine the elastic properties of nanocomposites using finite element modeling (FEM) (Alexander and Tzeng 1997;Robertson et al 1992;Lu 1997a, b). A method for investigating the mechanical response of heterogeneous materials with embedded circular inclusions was demonstrated by Liu and Chiou (2004).…”