Failure of short carbon-fiber-reinforced PEEK composites under high strain rate biaxial loading. (December 2022)

• Record Type: Journal Article
• Authors: Kang, Huaipu; Li, Yi; Liang, Jintao; Thomson, Daniel; Cui, Hao; Li, Yulong
• Is Part Of: Composites. Number 247(2022)
• Publication Date: 2022-12
• Subjects: A. Polymer-matrix composites (PMCs) -- B. Fracture -- B. Impact behavior -- C. Finite element analysis (FEA); Composite materials -- Periodicals; Materials science -- Periodicals; Composite materials; Periodicals; Electronic journals; 620.118
• DOI: 10.1016/j.compositesb.2022.110356
• Languages: English
• ISSNs: 1359-8368

Abstract

Abstract: The dynamic failure of short carbon fiber reinforced polyether-ether-ketone (SCFR-PEEK) composites under biaxial stresses was investigated in this paper. Cruciform specimens were loaded with a biaxial split Hopkinson tensile bar system, and a high-speed camera was utilized to record the deformation and failure processes. A nonlinear numerical model calibrated with dynamic uniaxial tests was used to estimate the stress in the cruciform specimen, in conjunction with strain fields from digital image correlation (DIC) of high-speed camera images. The failure of the cruciform specimen initiated inside the gauge section under all dynamic loading cases, and the numerical strain fields are in good agreement with the experimental ones. The dynamic failure envelope under biaxial stresses was successfully obtained, the failure strain decreased and failure stress increased with strain rate noticeably. The testing method developed here is also applicable for dynamic biaxial testing of many other composites. Graphical abstract: Image 1 Highlights: The failure of the cruciform specimens is confirmed to initiate inside the gauge section. A rate-dependent constitutive model calibrated with unidirectional tests is developed to estimate the biaxial stresses. The dynamic failure strain and stress envelopes in the tension-tension regime have been successfully obtained. The predicting accuracy of the Tsai-Wu failure criterion highly depends on the interaction coefficient F 12 .