Analysis of in-plane compression failure mechanism in carbon fiber braided composite with different off-axial angles

Abstract

This paper focuses on the in-plane compression mechanism of two-dimensional biaxial braided composite laminates under quasi-static compression and dynamic compression. Three types of specimens with different off-axial angles in respect of OA00, OA60, and OA90 were employed for compression experiments. The surface damage process of the specimen was recorded using optical camera and infrared thermal imaging technology. The internal damage morphology of the tested specimens was analyzed by X-ray computed tomography. The progressive damage behavior of braiding yarns and matrix resin was simulated by a three-dimensional meso-level finite element model. Experimental and simulation results revealed that the off-axial angle significantly affects mechanical properties and damage mechanisms. The stress distribution and compression deformation of braiding yarns are affected by the boundary conditions of load-bearing yarn, which relies on the off-axial angle. The stress of OA00 specimen is concentrated at the interface of yarn and matrix resin. The failure mode of OA00 specimen is dominated by the shear band, which is induced by the interface microcracks between yarn and matrix resin. The stress of OA60 and OA90 specimens are concentrated at the undulation position of the braiding yarn. The critical failure mode of OA60 and OA90 specimens is delamination induced by interlaminar microcracks. The OA60 specimen achieves a better compression response with respect to bearing the load and absorbing the fracture energy because the sub-laminate that is formed after delamination can continue to bear the load until its intralaminar fracture occurs.

Effect of stacking angles on crashworthiness of CFRP square tubes considering low-velocity impact damage

“…An in-depth understanding of the effects of low-velocity impact on the structural properties of composites is important for the practical application of composites. The mechanical properties of the composite materials have been 1 studied in depth, [37][38][39][40][41] Liu et al, 42 Guynn et al 43 and Soutis et al 44 studied the compression damage of open-cell CFRP laminates from a micromechanical point of view and found that for open-cell CFRP structures, the initial damage tends to arise from the edge of the hole and then expands steadily until a critical size is reached. Hallet et al, 45 Kumar et al 46 and Liu et al 42 investigated the effects of hole size, hole shape, hole size shape and distribution on CFRP failure modes and failure characteristics.…”

Influence of the bevel and steeple triggers on crashworthiness of carbon fiber-reinforced composite channel section structure

“…Carbon fiber-reinforced composites have gradually replaced metal materials in aerospace because of their excellent properties such as high specific strength, and high specific stiffness. [1][2][3][4][5][6][7][8] The crashworthiness of the aircraft is closely related to the design of the composite energy-absorbing structure, which directly affects the safety of the occupants. [9][10][11][12] In collision accidents, the composite structure can dissipate a large amount of impact kinetic energy through complex failure modes such as fiber matrix damage, buckling failure, delamination, and folding.…”