Cumulative fatigue damage for 3-D angle-interlock woven composite under three-point bending cyclic loading

2012 ◽  
Vol 22 (1) ◽  
pp. 3-16 ◽  
Author(s):  
Limin Jin ◽  
Baozhong Sun ◽  
Bohong Gu
Keyword(s):  
Cyclic Loading ◽  
Fatigue Damage ◽  
Stress Level ◽  
Three Dimensional ◽  
Woven Composite ◽  
Damage Development ◽  
Static Test ◽  
Three Point Bending ◽  
Cumulative Fatigue Damage ◽  
Number Of Cycles

This article presents the quantitative characterization of cumulative fatigue damage behavior for the three-dimensional angle-interlock woven composite undergoing three-point bending cyclic loading. The S–N curve was obtained to demonstrate the fatigue life of the three-dimensional angle-interlock woven composite under different stress levels. The increment of cycles for each 5% interval of stress level was reported to show the difference of fatigue resistance performances of the three-dimensional angle-interlock woven composite among the high, middle, and low intervals of stress level. In addition, the Cumulative Fatigue Damage versus Number of Cycles (D–N) curve and the Deflection Index versus Number of Cycles (F–N) curve were deduced to characterize the three-stage cumulative fatigue damage. Furthermore, the damage morphologies of the three-dimensional angle-interlock woven composite after fatigue tests were photographed to compare with those in quasi-static test. The cracks initiation and propagation in the three-dimensional angle-interlock woven composite during the process of cyclic loading were summarized to find the mechanisms of fatigue damage development.

Fatigue Damage Evaluation in CFRP Woven Fabric Composites Through Dynamic Modulus Measurements

2004 ◽  
Author(s):  
Hideaki Kasano ◽  
Osamu Hasegawa ◽  
Chiaki Miyasaka
Keyword(s):  
Fatigue Damage ◽  
Material Properties ◽  
Elastic Moduli ◽  
Fatigue Loading ◽  
Damage Function ◽  
Fatigue Tests ◽  
Woven Fabric ◽  
Damage Development ◽  
Dynamic Elastic Moduli ◽  
Number Of Cycles

Advanced fiber reinforced composite materials offer substantial advantages over metallic materials for the structural applications subjected to fatigue loading. With the increasing use of these composites, it is required to understand their mechanical response to cyclic loading [1–4]. Our major concern in this work is to macroscopically evaluate the damage development in composites during fatigue loading. For this purpose, we examine what effect the fatigue damage may have on the material properties and how they can be related mathematically to each other. In general, as the damage initiates in composite materials and grows during cyclic loading, material properties such as modulus, residual strength and strain would vary and, in many cases, they may be significantly reduced because of the progressive accumulation of cracks. Therefore, the damage can be characterized by the change in material properties, which is expected to be available for non-destructive evaluation of the fatigue damage development in composites. Here, the tensiontension fatigue tests are firstly conducted on the plain woven fabric carbon fiber composites for different loading levels. In the fatigue tests, the dynamic elastic moduli are measured on real-time, which will decrease with an increasing number of cycles due to the degradation of stiffness. Then, the damage fimction presenting the damage development during fatigue loading is determined from the dynamic elastic moduli thus obtained, from which the damage function is formulated in terms of a number of cycles and an applied loading level. Finally, the damage function is shown to be applied for predicting the remaining fifetime of the CFRP composites subjected to two-stress level fatigue loading.

Cumulative Damage in Composites

1990 ◽  
Vol 112 (3) ◽  
pp. 358-361 ◽  
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.

scholarly journals Study on the Influence of Different Prophase Stress Levels on the Fatigue Damage Characteristics of Granite

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Tianzuo Wang ◽  
Mengya Xue ◽  
Peng Sha ◽  
Fei Xue ◽  
Linxiang Wang
Keyword(s):  
Fatigue Damage ◽  
Stress Level ◽  
Development Trend ◽  
Cyclic Stress ◽  
Tangent Modulus ◽  
Dissipated Energy ◽  
Upper Limit ◽  
Stress Levels ◽  
Number Of Cycles ◽  
The Development Trend

In order to reveal the influence of prophase stress levels on the fatigue damage characteristics of granite, uniaxial fatigue tests of granite with different prophase stress levels were carried out on the basis of the MTS 815.04 rock mechanics test system. The results show that, under the same number of cycles, the failure degree increases with the increase of the prophase stress level. Under the low upper limit of cyclic stress, the tangent modulus and dissipated energy increase significantly with the increase of prophase stress level at the early stage of the cycle loading, while the increasing trend is not obvious with the increase of prophase stress level at the late stage. Under the high upper limit of cyclic stress, the tangent modulus and dissipated energy are less affected by the prophase stress level. The development trend of elastic release energy is not obvious with the increase of prophase stress level, which is less affected by the number of cycles. From the damage parameters defined by dissipative energy, under the low upper limit of cyclic stress, the initial damage is less affected by the prophase stress level. With the increase of the number of cycles, the influence of the prophase stress level on the development trend of the damage variable increases gradually. And the development trend of damage variables shows “C-shaped” damage.

The Reliability of a Component Under Several Distributed Cyclic Numbers at the Corresponding Constant Cyclic Stress Levels

2017 ◽  
Vol 4 (2) ◽  
Author(s):  
Xiaobin Le
Keyword(s):  
Cyclic Loading ◽  
Fatigue Damage ◽  
Cyclic Stress ◽  
New Method ◽  
Reliability Calculation ◽  
Stress Levels ◽  
Relative Errors ◽  
Number Of Cycles ◽  
Unsolved Issue ◽  
Loading Spectrum

The probabilistic stress-number of cycles curve (P-S-N curve) approach is widely accepted for describing the fatigue strengths of materials. It is also a widely accepted fatigue theory for determining the reliability of a component under fatigue loadings. However, it is an unsolved issue in the P-S-N curve approach that the calculation of reliability of a component under several distributed cyclic numbers at the corresponding constant cyclic stress levels. Based on the commonly accepted concept of the equivalent fatigue damage, this paper proposes a new method to determine the reliability of the component under several distributed cyclic numbers at the corresponding constant cyclic stress levels. Four examples including two validation examples will be provided to demonstrate how to implement the proposed method for reliability calculation under such fatigue cyclic loading spectrum. The relative errors in validation examples are very small. So, the proposed method can be used to evaluate the reliability of a component under several distributed cyclic number at different stress levels.

scholarly journals Numerical and Experimental Investigation of Cumulative Fatigue Damage under Random Dynamic Cyclic Loads of Lattice Structures Manufactured by Laser Powder Bed Fusion

Metals ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1395
Author(s):  
Marco Pisati ◽  
Marco Giuseppe Corneo ◽  
Stefano Beretta ◽  
Emanuele Riva ◽  
Francesco Braghin ◽  
...  
Keyword(s):  
Fatigue Damage ◽  
Structural Integrity ◽  
Failure Time ◽  
Face Centered Cubic ◽  
Lattice Structures ◽  
Random Vibrations ◽  
Vibration Fatigue ◽  
Lightweight Engineering ◽  
Cumulative Fatigue Damage ◽  
Number Of Cycles

Lattice structures are lightweight engineering components suitable for a great variety of applications, including those in which the structural integrity under vibration fatigue is of paramount importance. In this work, we experimentally and numerically investigate the dynamic response of two distinct lattice configurations, in terms of fatigue damage and life. Specifically, Face-Centered-Cubic (FCC) and Diamond lattice-based structures are numerically studied and experimentally tested under resonant conditions and random vibrations, until their failure. To this end, Finite Element (FE) models are employed to match the dynamic behavior of the system in the neighborhood of the first natural frequency. The FE models are employed to estimate the structural integrity by way of frequency and tip acceleration drops, which allow for the identification of the failure time and a corresponding number of cycles to failure. Fatigue life under resonant conditions is well predicted by the application of conventional multiaxial high cycle fatigue criteria to the local state of stress. The same approach, combined with the Rainflow algorithm and Miner’s rule, provides good results in predicting fatigue damage under random vibrations.

scholarly journals New Nonlinear Cumulative Fatigue Damage Model Based on Ecological Quality Dissipation of Materials

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Hongsong Li ◽  
Yongbao Liu ◽  
Xing He ◽  
Wangtian Yin
Keyword(s):  
Fatigue Life ◽  
Cyclic Loading ◽  
Fatigue Damage ◽  
Damage Model ◽  
Fatigue Loading ◽  
Ecological Quality ◽  
Aircraft Structures ◽  
Variable Amplitude ◽  
Fatigue Damage Accumulation ◽  
Cumulative Fatigue Damage

The failure of many aircraft structures and materials is caused by the accumulation of fatigue damage under variable-amplitude cyclic loading wherein the damage evolution of materials is complicated. Therefore, to study the cumulative fatigue damage of materials under variable-amplitude cyclic loading, a new nonlinear fatigue damage accumulation model is proposed based on the ecological quality dissipation of materials by considering the effects of load interaction and sequence. The proposed new model is validated by the test data obtained for three kinds of material under multilevel fatigue loading. Compared with the Miner model and Kwofie model, the proposed model can more effectively analyse the accumulative damage and predict fatigue life of different materials under variable-amplitude cyclic loading than others. The study provides a basis for predicting fatigue life accurately and determining reasonable maintenance periods of aircraft structures.

scholarly journals Probabilistic Modeling of Fatigue Damage Accumulation for Reliability Prediction

2011 ◽  
Vol 2011 ◽  
pp. 1-10 ◽  
Author(s):  
Vijay Rathod ◽  
Om Prakash Yadav ◽  
Ajay Rathore ◽  
Rakesh Jain
Keyword(s):  
Fatigue Damage ◽  
Stress Level ◽  
Damage Accumulation ◽  
Probabilistic Modeling ◽  
Nonstationary Process ◽  
Reliability Prediction ◽  
Fatigue Damage Accumulation ◽  
Cumulative Fatigue Damage ◽  
Single Stress ◽  
Level Loading

A methodology for probabilistic modeling of fatigue damage accumulation for single stress level and multistress level loading is proposed in this paper. The methodology uses linear damage accumulation model of Palmgren-Miner, a probabilistic S-N curve, and an approach for a one-to-one transformation of probability density functions to achieve the objective. The damage accumulation is modeled as a nonstationary process as both the expected damage accumulation and its variability change with time. The proposed methodology is then used for reliability prediction under single stress level and multistress level loading, utilizing dynamic statistical model of cumulative fatigue damage. The reliability prediction under both types of loading is demonstrated with examples.

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