Damage evolution of 3D woven carbon/epoxy composites under the tension–compression fatigue loading based on multi damage information

In recent decades the use of structural adhesive joints in the aerospace industry has increased considerably thanks to their high strength-to-weight ratio, low stress concentration and capacity to join different adherends. There is increasing interest in damage due to low-velocity impacts produced in adhesively bonded components and structures by vibrating loads. This type of loading is known as impact fatigue. The main aim of this paper is to investigate damage evolution in adhesive joints subjected to impact-fatigue and to compare this with damage evolution in standard fatigue (i.e. non-impacting, constant amplitude, sinusoidal fatigue). In this work, adhesively bonded lap joints were subjected to multiple tensile impacts tensile and it was seen that this type of loading was extremely damaging compared to standard fatigue. A number of methods of studying damage evolution in bonded joints subjected to fatigue and impact fatigue loading have been investigated and various parameters have been used to characterise these processes. Two modifications of the accumulated time-stress model [1-4] are proposed and it is shown that both models provide a suitable characterization of impact-fatigue in bonded joints.

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Fatigue Behavior of Impacted Plain-Weave Glass/Epoxy Composites under Tensile Fatigue Loading

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.297-300.1291 ◽

2005 ◽

Vol 297-300 ◽

pp. 1291-1296 ◽

Cited By ~ 1

Author(s):

Ki Weon Kang ◽

Jung Kyu Kim ◽

Heung Seob Kim

Keyword(s):

Fatigue Life ◽

Impact Damage ◽

Fatigue Behavior ◽

Fatigue Loading ◽

Epoxy Composites ◽

Low Velocity Impact ◽

Low Velocity ◽

Damage Behavior ◽

Plain Weave ◽

The Impact

The goals of this paper are to identify the impact damage behavior of plain-weave E-glass/epoxy composites and predict the fatigue life of the composites with impact-induced damage under constant amplitude loading. To identify these behaviors, the low velocity impact and fatigue after impact tests are performed for glass/epoxy composites having two types of fiber orientations. The impact damage behavior is dependent on the fiber orientation of the composites. The fatigue life of the impacted composites can be identified through the prediction model, which was proposed on the carbon/epoxy laminates by authors regardless of fiber orientations.

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Cumulative Damage in Composites

Journal of Engineering Materials and Technology ◽

10.1115/1.2903338 ◽

1990 ◽

Vol 112 (3) ◽

pp. 358-361 ◽

Cited By ~ 28

Author(s):

H. A. Whitworth

Keyword(s):

Experimental Data ◽

Fatigue Damage ◽

Stress Level ◽

Present Model ◽

Damage Model ◽

Fatigue Loading ◽

Damage Function ◽

Epoxy Composites ◽

Remaining Life ◽

Cumulative Fatigue Damage

The problem of cumulative fatigue damage in composites is analyzed based upon the development of a phenomenological damage model. In this modeling, a damage function is defined based on the degradation of the residual stiffness and used to predict the remaining life of composite specimens subjected to dual stress level fatigue loading. Available experimental data for graphite/epoxy composites are compared with the predictions of the present model.

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