Numerical Simulation of Elastic-Plastic Behavior of Thermoplastic Composites

Journal of Thermoplastic Composite Materials

Shen

et al. 2007

Self Cite

In this study, the interlaminar stresses for a thick AS4-PEEK laminate [0/±45/90]2s for three different strain rates are computed and investigated using the finite element procedure developed with the finite element program generator (FEPG) of Beijing Fegensoft Corporation Limited. The three-dimensional distribution plots at different interfaces are given. According to the interlaminar stress results for three different strain rates, the effects of the strain rates on the interlaminar stresses at different interfaces are elucidated. The interlaminar shear stresses τzx at the interfaces increase along with an increase in strain rates, but when the strain rate reaches a certain extent, the effects of the strain rates on the interlaminar shear stresses are gradually weakened. The effects of the strain rates on the interlaminar shear stresses τzy at the interfaces are similar. Except for the interlaminar normal stresses at the interface +45%-45, their strain rate dependence effects are slight. As far as the different interfaces are concerned, the effects of the strain rates on the interlaminar stresses at the interface 0%90 are the weakest, and the effects on the interlaminar stresses at the interface +45%-45 are the strongest. Furthermore, the variation circumstances of the interlaminar stresses along the free edges are studied and the interlaminar stresses for two strain rates at this location are analyzed.

“…On the platform of FEPG, the above model which is not presented in the commercial codes at present is realized and the relative procedure is developed [8,9].…”

Section: Three-dimensional Elastic-plastic Model Of Thermoplastic Compositesmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Rate-dependence Analysis of Interlaminar Stresses of Thick Thermoplastic Composite AS4-PEEK Laminate

Journal of Thermoplastic Composite Materials

Shen

et al. 2007

Self Cite

“…They can be used over the range of temperature up to about 3008C, which is why they are typically used in the advanced aerospace structures despite the high cost. Continuous carbon-fiber-reinforced thermoplastics have already been evaluated in the commercial aerospace Figures 2,[4][5][6][7][8][9][10][11][12] appear in color online http://jtc.sagepub.com sector in the form of demonstrator components such as fuselage and air-foil skin structures [2]. Thermoplastic composites are used for complex structures where different components are often connected by bolts or rivets.…”

Section: Introductionmentioning

confidence: 99%

“…The fracture surfaces were analyzed through microscopic observation. Based on the previously developed 3D elastic-plastic procedure [11], finite element modeling for the notched AS4/PEEK laminate was carried out to interpret the experimental observations.…”

Section: Introductionmentioning

confidence: 99%

Fracture Characters and Damage Mechanism of the Notched AS4/PEEK Composite Laminate

Journal of Thermoplastic Composite Materials

Wang

et al. 2009

A uniaxial tension experiment was performed for the thermoplastic AS4/PEEK composite laminate with a circular hole. Ultimately the specimen fractured in the vicinity of the minimum cross section of the laminate. Through micro-observation with the OLYMPUS micro-system, the fracture characters and sub-critical damages were captured. It can be concluded that delamination and matrix cracks occurred prior to final failure of the laminate. Furthermore, a numerical simulation for the notched laminacte under uniaxial tension was implemented with a 3D elastoplasticity model to interpret the damage mechanism of the notched laminate.

“…Weeks and Sun [7] proposed a three-dimensional elastic-plastic model which can simulate the nonlinear behavior and the strain-rate dependence behavior well. Ding et al [8,9] introduced this model into the finite element generating system (FEPG) and developed the relative procedure; the procedure was verified by comparing the computation results with the reference experimental ones. The distribution characteristics of the interlaminar stresses of different AS4/PEEK composite laminates were analyzed by Ding et al [10][11][12].…”

Section: Introductionmentioning

confidence: 99%

Effects of the Strain Rate Variation on the Interlaminar Stresses of the Thick Angle-ply Laminates

Journal of Reinforced Plastics and Composites

Huo

et al. 2007

Self Cite

In this paper, for the thick AS4/PEEK angle-ply laminate [±25]s4, the interlaminar stresses for four different strain rates are computed and investigated. The three-dimensional distribution plots at different interfaces are given. According to the interlaminar stress results for four different strain rates, the effects of the strain rates on the interlaminar stresses at different interfaces are elucidated. The absolute values of the interlaminar shear stresses τzx at the interfaces +25°/-25° and -25°/+25° increase along with increase of strain rates. The effects of the strain rates on the interlaminar shear stresses τzy at the interfaces are similar. For the interlaminar normal stresses at the interfaces +25°/-25° and -25°/+25°, if the stresses are tensile ones, their values rise along with increment of the strain rates; however, if they are compressive stresses, the contrary effects exist. Furthermore, the variation circumstances of the interlaminar stresses along the thickness are studied, and the interlaminar stresses for four strain rates at this location are analyzed. It can be obtained that the interlaminar stresses closer to the free edges at the interfaces are most evidently influenced by the strain rates.