Fracture morphology of carbon fiber reinforced plastic composite laminates

Abstract

Carbon fiber reinforced plastic (CFRP) composites have been extensively used in fabrication of primary structures for aerospace, automobile and other engineering applications. With continuous and widespread use of these composites in several advanced technology, the frequency of failures is likely to increase. Therefore, to establish the reasons for failures, the fracture modes should be understood thoroughly and unambiguously. In this paper, CFRP composite have been tested in tension, compression and flexural loadings; and microscopic study with the aid of Scanning Electron Microscope (SEM) has been performed on failed (fractured) composite surfaces to identify the principle features of failure. Efforts have been made in correlating the fracture surface characteristics to the failure mode. The micro-mechanics analysis of failure serves as a useful guide in selecting constituent materials and designing composites from the failure behavior point of view. Also, the local failure initiation results obtained here has been reliably extended to global failure prediction.

Environmental Durability Enhancement of Natural Fibres Using Plastination: A Feasibility Investigation on Bamboo

“…Energy dispersive x-ray spectroscopy (EDS) (Oxford Instruments NanoAnalysis, Concord, MA, USA) was conducted on different cross-sections of a plastinated bamboo culm to calculate the amount of silicone flowing into the bamboo. The cross-sections of the bamboo samples were coated with a platinum layer to enable conduction of electrical current [22]. The platinum sputtering thickness was about 6e-6 to 8e-6 m. A Tescan Mira 3 XMU Scanning Electron Microscope was used for the visual investigations.…”

Effect of carbon fibres on the static and fatigue mechanical properties of fibre metal laminates

“…Fatigue cracks were initiated from the crack origin induced by the cutting process, followed by propagation to the Ti‐alloy facesheet that was characterized by fatigue striations, and this finally led to a ductile fracture, which is characterized by dimple features (Figures D‐F). However, a relatively flat fracture surface was observed for the epoxy matrix in K13D CFRP, which differed from the tensile fracture surface of the unidirectional PAN‐based CFRP . The appearance of a flat region in the epoxy matrix corresponds to the stable growth of cracks during fatigue.…”

Mechanisms of Friction and Wear Reduction by Carbon Fiber Reinforcement of PEEK

“…This idea is in agreement with the view that shearing is the dominating mechanism in the friction of carbon fibers. Carbon fibers can fail in different modes depending on the loading conditions [25]. Under tribological loading, cracking, thinning, and debonding of carbon fibers are believed to be the relevant mechanisms [7].…”