Small‐sized specimen design with the provision for high‐frequency bending‐fatigue testing

The bending fatigue strength of 17CrNi6-6 steel subjected to vacuum carburizing with high pressure gas hardening has been measured using a novel high-frequency technique. The test records the changes in resonance and consists of observing resonance frequency changes in a vibrating system with a single degree of freedom as a result of the forming of a fatigue crack. Moreover, a mechanism of fatigue nucleation and propagation in steel hardened by vacuum carburizing is presented.

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Tracked Changes. Metallic materials � Rotating bar bending fatigue testing

10.3403/30404147 ◽

2021 ◽

Keyword(s):

Fatigue Testing ◽

Metallic Materials ◽

Bending Fatigue

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Fatigue of Metal Free Reed due to Self-Excited Oscillation

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.33-37.267 ◽

2008 ◽

Vol 33-37 ◽

pp. 267-272

Author(s):

Yoshinobu Shimamura ◽

Keiichiro Tohgo ◽

Hiroyasu Araki ◽

Yosuke Mizuno ◽

Shoji Kawaguchi ◽

...

Keyword(s):

Fatigue Testing ◽

The Self ◽

Fatigue Properties ◽

Bending Fatigue ◽

Metal Free ◽

Mass Damper ◽

Excited Oscillation ◽

Analytical Research ◽

Fatigue Characteristics ◽

Good Agreement

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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Improvement of Fatigue Behaviour of High Strength Aluminium Alloys by Fluidized Bed Peening (FBP)

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.344.87 ◽

2007 ◽

Vol 344 ◽

pp. 87-96 ◽

Cited By ~ 2

Author(s):

M. Barletta ◽

F. Lambiase ◽

Vincenzo Tagliaferri

Keyword(s):

Fatigue Life ◽

Fluidized Bed ◽

Fatigue Testing ◽

Fatigue Behavior ◽

Maximum Amplitude ◽

High Strength ◽

Operational Parameters ◽

Bending Fatigue ◽

Rotating Bending Fatigue ◽

Rotating Bending

This paper deals with a definition of a relatively novel technique to improve the fatigue behavior of high strength aluminum alloys, namely, Fluidized Bed Peening (FBP). Fatigue samples made from AA 6082 T6 alloy were chosen according to ASTM regulation about rotating bending fatigue test and, subsequently, treated by varying FBP operational parameters and fatigue testing conditions. First, a full factorial experimental plan was performed to assess the trend of number of cycles to rupture of fatigue samples varying among several experimental levels the factors peening time and maximum amplitude of alternating stress applied to fatigue samples during rotating bending fatigue tests. Second, design of experiment (DOE) technique was used to analyze the influence of FBP operational parameters on fatigue life of AA 6082 T6 alloy. Finally, ruptures of FB treated samples and untreated samples were discussed in order to evaluate the influence of operational parameters on the effectiveness of FBP process and to understand the leading process mechanisms. At any rate, the fatigue behavior of processed components was found to be significantly improved, thereby proving the suitability of FBP process as alternative mechanical technique to enhance fatigue life of components made from high strength aluminum alloy.

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Design of High Frequency Fatigue Testing Machine Driven by Piezoelectric Vibrator

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.220-223.543 ◽

2012 ◽

Vol 220-223 ◽

pp. 543-548

Author(s):

Meng Jie ◽

Hai Feng Xie ◽

Yan Liu ◽

Zhi Gang Yang

Keyword(s):

High Frequency ◽

Fatigue Testing ◽

Testing Machine ◽

Fatigue Property ◽

Maximum Load ◽

Load Level ◽

Piezoelectric Resonance ◽

Piezoelectric Vibrator ◽

Plate Spring ◽

Working Principle

In order to measure the fatigue property of the small and hard brittle components working under conditions of the little amplitude, high frequency force, a novel kind of resonant high frequency fatigue testing machine which is driven by the piezoelectric vibrator (PZT、PLZT or PMN) has been proposed. Firstly, the working principle of the piezoelectric resonance high frequency fatigue testing machine is analyzed, and the dynamic model of the fatigue testing machine is established to get the systemic dynamic characteristics. Then a prototype is designed and produced. Finally, the maximum load on the sample is measured by the test with the machine. The results indicate that the maximum load on the sample is 23.4N-98.1N when changing the voltage (100V-250V) and the thickness of the plate spring (1.1mm-0.6mm). The prototype made in this paper is suitable for the tensile and fatigue testing with the load level mentioned above under the condition of little amplitude and high frequency force.

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Test Method for Bending Fatigue Testing for Copper-Alloy Spring Materials

10.1520/b0593-21 ◽

2021 ◽

Author(s):

Keyword(s):

Copper Alloy ◽

Fatigue Testing ◽

Test Method ◽

Bending Fatigue

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A Novel Prediction Perspective to the Bending Over Sheave Fatigue Lifetime of Steel Wire Ropes by Means of Artificial Neural Networks

Artificial Intelligence and Machine Learning Applications in Civil, Mechanical, and Industrial Engineering - Advances in Computational Intelligence and Robotics ◽

10.4018/978-1-7998-0301-0.ch003 ◽

2020 ◽

pp. 39-58

Author(s):

Tuğba Özge Onur ◽

Yusuf Aytaç Onur

Keyword(s):

Neural Networks ◽

Artificial Neural Networks ◽

Fatigue Testing ◽

Steel Wire ◽

Experimental Studies ◽

Fatigue Lifetime ◽

Bending Fatigue ◽

Wire Ropes ◽

Significant Case ◽

Artificial Neural

Steel wire ropes are frequently subjected to dynamic reciprocal bending movement over sheaves or drums in cranes, elevators, mine hoists, and aerial ropeways. This kind of movement initiates fatigue damage on the ropes. It is a quite significant case to know bending cycles to failure of rope in service which is also known as bending over sheave fatigue lifetime. It helps to take precaution in the plant in advance and eliminate catastrophic accidents due to usage of rope when allowable bending cycles are exceeded. To determine bending fatigue lifetime of ropes, experimental studies are conducted. However, bending over sheave fatigue testing in laboratory environments require high initial preparation cost and longer time to finalize the experiments. Due to those reasons, this chapter focuses on a novel prediction perspective to the bending over sheave fatigue lifetime of steel wire ropes by means of artificial neural networks.

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