DAMAGE PROPAGATION AND THERMOGRAPHY IN DISCONTINUOUS CARBON FIBER COMPOSITE (DCFC) UNDER TENSILE (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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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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Non-destructive characterization of carbon fiber composite/Cu joints for nuclear fusion applications

Fusion Engineering and Design ◽

10.1016/j.fusengdes.2008.04.005 ◽

2008 ◽

Vol 83 (5-6) ◽

pp. 702-712 ◽

Cited By ~ 11

Author(s):

Valentina Casalegno ◽

Milena Salvo ◽

Monica Ferraris ◽

Federico Smeacetto ◽

Mario Merola ◽

...

Keyword(s):

Carbon Fiber ◽

Fiber Composite ◽

Nuclear Fusion ◽

Carbon Fiber Composite ◽

Fusion Applications ◽

Non Destructive ◽

Non Destructive Characterization

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Mechanical Properties and Tensile Fatigue of Graphene Nanoplatelets Reinforced Polymer Nanocomposites

Journal of Nanomaterials ◽

10.1155/2013/565401 ◽

2013 ◽

Vol 2013 ◽

pp. 1-9 ◽

Cited By ~ 32

Author(s):

Ming-Yuan Shen ◽

Tung-Yu Chang ◽

Tsung-Han Hsieh ◽

Yi-Luen Li ◽

Chin-Lung Chiang ◽

...

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Fatigue Life ◽

Carbon Fiber ◽

Ultimate Tensile Strength ◽

Composite Laminates ◽

Epoxy Composite ◽

Fiber Composite ◽

Graphene Nanoplatelets ◽

Carbon Fiber Composite

Graphene nanoplatelets (GNPs) are novel nanofillers possessing attractive characteristics, including robust compatibility with most polymers, high absolute strength, and cost effectiveness. In this study, GNPs were used to reinforce epoxy composite and epoxy/carbon fiber composite laminates to enhance their mechanical properties. The mechanical properties of GNPs/epoxy nanocomposite, such as ultimate tensile strength and flexure properties, were investigated. The fatigue life of epoxy/carbon fiber composite laminate with GPs-added 0.25 wt% was increased over that of neat laminates at all levels of cyclic stress. Consequently, significant improvement in the mechanical properties of ultimate tensile strength, flexure, and fatigue life was attained for these epoxy resin composites and carbon fiber-reinforced epoxy composite laminates.

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