Evaluation of the effect of MWCNT amount and dispersion on bending fatigue properties of non-crimp CFRP composites

Metal free reeds are used for musical instruments like harmonica. Free reeds are small, thin cantilevers, and oscillate by blowing air. It is reported that free reeds break due to fatigue during play. In order to elongate the life of free reeds, the fatigue properties should be investigated and a motion analysis method should be developed. The experimental and analytical research on metal free reed, however, has been rarely reported. In this study, two types of fatigue testing machines were developed to obtain basic fatigue characteristics. The fatigue testing machines are designed for bending fatigue of actual free reeds whose thickness is less than 400 μm. An S-N diagram is successfully obtained up to 107 cycles by using the developed fatigue testing machines. The fracture surfaces of fatigued specimens are in good agreement with those of free reeds failed in use. Then, an analytical method for the self-excited oscillation of free reeds was developed based on a mass-damper-spring model. The proposed method can take account for the shape of free reed. The self-excited oscillation of free reeds with different shape are analyzed and in good agreement with experimental results.

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High-temperature bending fatigue properties of oxide dispersion-strengthened platinum–rhodium alloy under high axial stress

International Journal of Fatigue ◽

10.1016/j.ijfatigue.2019.105385 ◽

2020 ◽

Vol 132 ◽

pp. 105385 ◽

Cited By ~ 1

Author(s):

A. Niwa ◽

Y. Akita ◽

K. Enomoto ◽

R. Aoyama ◽

H. Akebono ◽

...

Keyword(s):

High Temperature ◽

Axial Stress ◽

Oxide Dispersion Strengthened ◽

Fatigue Properties ◽

Oxide Dispersion ◽

Bending Fatigue

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Study on Fatigue Test and Life Prediction of Polyurethane Cement Composite (PUC) under High or Low Temperature Conditions

Advances in Materials Science and Engineering ◽

10.1155/2020/2398064 ◽

2020 ◽

Vol 2020 ◽

pp. 1-14

Author(s):

Hongshuai Gao ◽

Quansheng Sun

Keyword(s):

Fatigue Life ◽

Fatigue Test ◽

Asphalt Mixture ◽

Cement Composite ◽

Control Mode ◽

Fatigue Properties ◽

Coupling Condition ◽

Bending Fatigue ◽

Bending Fatigue Test ◽

Steel Deck

There are many diseases in the deck pavement of long-span steel bridges under the action of vehicles, rainwater, and freezing. It is necessary to study a new type of pavement material with high waterproof property, light weight, and high bonding performance for steel deck pavement. Polyurethane cement composite (PUC) can be used for steel deck pavement. In order to find out the temperature effect on fatigue properties of PUC, the four-point bending fatigue test was carried out at different temperatures. In this paper, the optimum mix ratio of PUC was selected by compressive and flexural tests, and then the bending fatigue test was conducted under strain control mode. Under temperature and external force coupling condition, a method for predicting fatigue life of PUC is proposed by the combination of theoretical deduction and experimental research. The results show that the proposed formula can effectively describe the fatigue life and fatigue limit of PUC. Finally, compared with three different asphalt mixtures for steel deck pavement, it is found that the fatigue performance of polyurethane cement is better than that of asphalt mixture.

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