Papers by Keyword: Woven Composite

Abstract: In this study, development of a decoupled multiscale analysis method for woven composites is conducted. To this end, an elastic-viscoplastic macroscopic constitutive model which is able to express strong anisotropy of composites is introduced, and the material parameters in the constitutive model are determined based on the results of triple-scale homogenization analysis. Moreover, the constitutive model is implemented in the finite element analysis code LS-DYNA. The developed method is applied to 3-point bending analysis of plain-woven carbon fiber-reinforced plastic (CFRP) composites with various types of laminates configurations. It is shown that the present method can analyze their different behavior depending on the laminate configuration with greatly reduced computational costs.

Abstract: Process induced residual stresses in thermoset composite parts is one of significant issue faced by the industry. Its Modelling is a coupled multiphysics phenomena. Precise information about the chemical shrinkage, thermal expansion coefficient, cure kinetics, heat transfer and constitutive equation are required for an accurate simulation. In this article, spring-in angle induced in woven carbon/epoxy composite bracket is modelled by solving the thermo-kinetics and thermo-mechanics coupling simultaneously in a commercial finite element software. The obtained values of spring-in angle using numerical simulation are compared with those found in the literature and both are found in agreement.

Abstract: A numerical investigation is performed to study the free vibration responses of a width tapered composite beam. The finite element simulation is performed to investigate the effect of taper angle along the longitudinal plane of the beam on the free transverse vibration responses. Experimental investigations are also performed to demonstrate the effectiveness of the developed finite element formulation (FEM) in identifying the free vibration responses of the uniform and tapered composite beam. Further, various parametric studies are performed to investigate the effect of taper angle and boundary conditions on natural frequencies of the uniform and tapered composite beams. It is shown that the natural frequencies of the taper configurations at all the modes considered are higher than those obtained from the uniform composite beam. It is concluded that the stiffness of the composite structures could be tailored according to the requirement by changing the taper angle of the composite along longitudinal plane to obtain the desired natural frequencies.

Abstract: In order to understand damage mechanism, the influences of lay-up construction of laminates and environgment on tension behavior of 2D woven composite laminates with an open-hole, which was manufactured by a new technology, uniaxial tension tests are performed in 3 different environments on 4 kinds of lay-up specimens, using a WE-50 electromechanical universal material testing machines. The fracture of specimens are analysed through micrographic observations. The result show that there is a large difference both in tensile strength and damage mechanism due to different kinds of lay-up specimens: 1) the tensile strength of specimens that only with ±45 degree laminated is much lower than other samples with different kinds of layup and its tensile stress-strain curves presents nonlinear; 2)The failure modes and damage mechanism determines the strength of specimens; 3)The change of environment had a certain effect on the mechanical behaviors of materials, in this paper, it will cause the tensile strength of speicmens decreasing.

Abstract: The present study focuses on the mechanical performance and damage evolution of woven fabric E-glass fiber reinforced epoxy composite (7781/F155-glass/epoxy). For the identical behavior in the 0o and the 90o directions of the tested material, the mechanical experiments were performed with 0o and 45o specimens. Three kinds of tests were implemented respectively: tension test with 0o specimen, compression test with 0o specimen, and tension test with 45o specimen which represents the in-plane shear test. Tension, compression and in-plane shear damage, which are defined as the decreasing ratio of modulus, were calculated from the data of quasi-static cyclic tests. The influence of loading rate on material behaviors were investigated under three different loading rates. Although all of the three loading rates are low, it showed that the strain rate has obvious effects on the ultimate strengths and moduli of the glass fiber reinforced epoxy composite.