CURVED PULTRUDED UNIDIRECTIONAL CARBON FIBER COMPOSITE UNDER INTERLAMINAR SHEAR FATIGUE LOADING

The discontinuous carbon fiber composite (DCFC) has a different damage behaviour due to non homogenuous sub structure. Consequently, monitoring and diagnosis of DCFC damage mechanisms require the application of a contactless method in real-time operation, i.e., non destructive method of thermography. The aim of this study is to investigate the damage propagation of DCFC material under tensile (fatigue) condition with non destructive testing (NDT) thermography method. Under fatigue testing, temperature evolutions were monitored by an Infra-Red (IR) camera. The results show that damage propagation and thermal response indicated the similar behaviour which consists of three stages. At the beginning, low temperature increased until ≈ 10% of fatigue life due to the initial damage. The initial damage propagated and the temperature reached the stable thermal state due to the saturation in the damage appearance of micro cracking of matrix and chip until ≈ 80% of fatigue life. At the last ≈ 20% of fatigue life, damage continued to propagate and provoked the occurrence of macro damage that induced the final failure indicated by highest peak of temperature. The analysis from the experiment results concluded that thermal response relates with the damage propagation of DCFC under fatigue loading.

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Effects of carbon nanotubes on the interlaminar shear strength and fracture toughness of carbon fiber composite laminates: a review

Journal of Materials Science ◽

10.1007/s10853-021-06734-z ◽

2022 ◽

Author(s):

Ce Zhang ◽

Guoli Zhang ◽

XiaoPing Shi ◽

Xi Wang

Keyword(s):

Carbon Nanotubes ◽

Fracture Toughness ◽

Shear Strength ◽

Carbon Fiber ◽

Composite Laminates ◽

Fiber Composite ◽

Interlaminar Shear Strength ◽

Carbon Fiber Composite ◽

Interlaminar Shear

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Secondary Raw Materials from Residual Carbon Fiber-Reinforced Composites by An Upgraded Pyrolysis Process

Polymers ◽

10.3390/polym13193408 ◽

2021 ◽

Vol 13 (19) ◽

pp. 3408

Author(s):

Alexander Lopez-Urionabarrenechea ◽

Naia Gastelu ◽

Alberto Jiménez-Suárez ◽

Silvia G. Prolongo ◽

Adriana Serras-Malillos ◽

...

Keyword(s):

Carbon Fiber ◽

Carbon Fibers ◽

Raw Materials ◽

Fiber Composite ◽

Tensile Modulus ◽

Recycling Process ◽

Carbon Fiber Composite ◽

Gaseous Stream ◽

Carbon Fiber Reinforced Composites ◽

Interlaminar Shear

This paper presents a process where carbon fibers and hydrogen can be recovered simultaneously through a two-stage thermal treatment of an epoxy-carbon fiber composite. For this purpose, some pieces of epoxy resin reinforced with carbon fiber fabrics have been fabricated and, after curing, have been pyrolyzed in an installation consisting of two reactors. In the first one, the thermal decomposition of the resin takes place, and in the second one, the gases and vapors coming from the first reactor are thermally treated. Once this process is completed, the solid generated is oxidized with air to eliminate the resin residues and carbonaceous products from the fibers surface. The recovered carbon fiber fabrics have been reused to make new cured parts and their electrical and mechanical properties have been measured. The results show that it is possible to obtain carbon fiber fabrics that can be processed as they leave the recycling process and that retain 80% of the tensile modulus, 70% of the flexural strength, and 50% of the interlaminar shear strength. At the same time, a gaseous stream with more than 66% by volume of hydrogen can be obtained, reaching a maximum of 81.7%.

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Experimental Investigation of the Three-point Bending Fatigue Properties of Carbon Fiber Composite Laminates

Advances in Material Science ◽

10.18686/ams.v1i1.1 ◽

2016 ◽

Vol 1 (1) ◽

pp. 1 ◽

Cited By ~ 8

Author(s):

Meihong He ◽

Tao Yang ◽

Xuejuan Niu ◽

Yu Du

Keyword(s):

Fatigue Life ◽

Carbon Fiber ◽

Stress Level ◽

Fiber Composite ◽

Fatigue Loading ◽

Fatigue Properties ◽

Loading Frequency ◽

Carbon Fiber Composite ◽

Bending Fatigue ◽

Three Point Bending

The three point bending fatigue properties of carbon fiber epoxy matrix composite laminates were compared for fatigue loading stress levels of 75, 80 and 85%, and fatigue loading frequencies of 10, 15 and 20Hz, respectively. The experimental results showed that: the bending fatigue life of the composites obviously decreased with the increase of the fatigue loading stress level or the loading frequency. The fatigue damage accumulation process could be divided into three distinct stages according to the accumulation rate: fast, slow and then fast. When the loading stress level was increased from 75 to 85%, the duration of the third stage decreased from 40 to 10% of the overall fatigue life. When the loading frequency was increased from 10 to 20Hz, the duration of the third stage increased from 20 to 40% of the overall fatigue life. Matrix cracking, fiber breaking, interface debonding and delamination were identified as the main three-point bending fatigue damage modes of the carbon fiber composite material, and the stress level and the loading frequency were found to significantly influence the fatigue failure properties of the composites.

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