A Newly Developed Multi-Harmonic Rotating Beam Fatigue Testing Machine

The purpose of this project is to build a prototype of compact flexural fatigue testing machine and to strive for an easy working-environment as required by the users besides cutting the cost of the machining. This particular project is about to build the prototype of compact flexural fatigue testing machine in compact mode. In this project, the prototype will be functioning 60% similar to the real fatigue machine which is Dynamic Fatigue Testing Machine (INSTRON) due to timer counter, frequency and load applied. But the new invention is this prototype was using the concept of electromagnetic force relay that will apply to the specimen using the application of basic electronics. The motion sensor also being applied to this prototype to achieve accurate results when the specimen breaks up after undergoes a fatigue failure.

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Surface Durability of Spur Gears at Hertzian Stresses Over Shakedown Limit

Journal of Engineering for Industry ◽

10.1115/1.3438338 ◽

1974 ◽

Vol 96 (2) ◽

pp. 359-372 ◽

Cited By ~ 1

Author(s):

Akira Ishibashi ◽

Taku Ueno ◽

Shigetada Tanaka

Keyword(s):

Fatigue Testing ◽

Testing Machine ◽

Carbon Steels ◽

Rolling Contact ◽

Hertzian Contact ◽

Load Testing ◽

Short Period ◽

Hertzian Contact Stress ◽

Surface Durability ◽

Shakedown Limit

Using a new type of gear-load testing machine and a disk-type rolling fatigue testing machine designed and made by the authors, the upper limits of Hertzian contact stress allowable on rolling contact surfaces were investigated. It was shown conclusively that gears and rollers made of soft carbon steels could be rotated beyond 108 revolutions at Hertzian stresses over shakedown limit (≈ 0.4 HB). In the case of gears, pits having a pitting area ratio of 0.04 percent occurred during 1.16 × 108 rotations at a Hertzian stress of 0.50 HB. However, no pitting occurred on the roller rotated through 1.20 × 108 revolutions at a Hertzian stress of 0.71 HB, although appreciable changes in texture were observed at the subsurface. In order to rotate gears or rollers at Hertzian stresses over shakedown limit, their surface must either be very smooth initially or after a short period of running, and an oil film must be formed between contacting surfaces.

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Fatigue testing machine for spring wire

Journal of the Franklin Institute ◽

10.1016/0016-0032(57)90235-1 ◽

1957 ◽

Vol 263 (6) ◽

pp. 544-545

Keyword(s):

Fatigue Testing ◽

Testing Machine ◽

Spring Wire

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On estimating axial high cycle fatigue behavior by rotating beam fatigue testing: Application to A356 aluminum alloy castings

Materials Science and Engineering A ◽

10.1016/j.msea.2017.05.008 ◽

2017 ◽

Vol 697 ◽

pp. 95-100 ◽

Cited By ~ 6

Author(s):

Hüseyin Özdeş ◽

Murat Tiryakioğlu ◽

Paul D. Eason

Keyword(s):

Aluminum Alloy ◽

High Cycle Fatigue ◽

Fatigue Testing ◽

Fatigue Behavior ◽

Cycle Fatigue ◽

A356 Aluminum Alloy ◽

Rotating Beam ◽

Alloy Castings ◽

A356 Aluminum

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Gigacycle Fatigue of Welded Joints of Structural Materials (A Review)

Advanced Engineering Forum ◽

10.4028/www.scientific.net/aef.17.14 ◽

2016 ◽

Vol 17 ◽

pp. 14-30 ◽

Cited By ~ 1

Author(s):

Okechukwu P. Nwachukwu ◽

Alexander V. Gridasov ◽

Ekaterina A. Gridasova

Keyword(s):

Fatigue Testing ◽

Fatigue Behavior ◽

Testing Machine ◽

Structural Materials ◽

Fatigue Tests ◽

Material Defects ◽

Graphite Cast Iron ◽

Ultrasonic Fatigue ◽

Materials Used ◽

Fatigue Failures

This review looks into the state of gigacycle fatigue behavior of some structural materials used in engineering works. Particular attention is given to the use of ultrasonic fatigue testing machine (USF-2000) due to its important role in conducting gigacycle fatigue tests. Gigacycle fatigue behavior of most materials used for very long life engineering applications is reviewed.Gigacycle fatigue behavior of magnesium alloys, aluminum alloys, titanium alloys, spheroid graphite cast iron, steels and nickel alloys are reviewed together with the examination of the most common material defects that initiate gigacycle fatigue failures in these materials. In addition, the stage-by-stage fatigue crack developments in the gigacycle regime are reviewed. This review is concluded by suggesting the directions for future works in gigacycle fatigue.

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Impacts of Thermal and Mechanical Cycles on Electro-Thermal Anti-Icing System of CFRP Laminates Embedding Sprayable Metal Film

Materials ◽

10.3390/ma14071589 ◽

2021 ◽

Vol 14 (7) ◽

pp. 1589

Author(s):

Rongjia Li ◽

Wang Xu ◽

Dalin Zhang

Keyword(s):

Fatigue Life ◽

Metal Film ◽

Fatigue Testing ◽

Aerodynamic Force ◽

Testing Machine ◽

Laminated Composite ◽

Heating Element ◽

Electric Resistance ◽

Potential Threat ◽

Mechanical Cycling

The aircraft electro-thermal anti-icing system that can guarantee flight safety may be affected by periodic heating and cyclic aerodynamic force during long-term flight missions, which seems to be a potential threat to ice protection. This paper aims to investigate the impacts of thermal and mechanical cycles on heating elements of the electro-thermal anti-icing system. Specimens were manufactured with CFRP (carbon fiber reinforced polymer) laminated composite, glass fiber prepreg and copper screen, in which sprayable metal film (SMF) was embedded as the heating element. The study focuses on electric resistance variation of SMF and functional fatigue life under the cycling load. Thermal cycling tests were carried out in an insulated chamber where the specimens were heated up to 80 °C and then cooled down to −55 °C for 1000 cycles. Mechanical cycling tests were conducted on a fatigue testing machine where the specimens were imposed on tension-compression loading for 106 cycles. Results showed that the electric resistance of SMF increased with the number of loading cycles. The resistance was increased by 20% and the heating power was decreased by 16.67% after 1000 thermal cycles. During the mechanical cycling tests, it was found that the heating element was destructed before the structural failure, which indicated that the fatigue life of function was lower than that of the structure.

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Experimental Evidence of Specimen-Size Effects on EN-AW6082 Aluminum Alloy in VHCF Regime

Applied Sciences ◽

10.3390/app11094272 ◽

2021 ◽

Vol 11 (9) ◽

pp. 4272

Author(s):

Stefano Invernizzi ◽

Francesco Montagnoli ◽

Alberto Carpinteri

Keyword(s):

Aluminium Alloy ◽

Cross Section ◽

Fatigue Testing ◽

Testing Machine ◽

Experimental Tests ◽

Theoretical Explanation ◽

Specimen Size ◽

Section Surface ◽

Middle Cross Section ◽

Ultrasonic Fatigue

The present paper investigates the influence of the specimen size of EN-AW6082 wrought aluminium alloy subjected to very high cycle fatigue (VHCF) tests. The hourglass specimens were tested under fully reversed loading condition, up to 109 cycles, by means of the ultrasonic fatigue testing machine developed by Italsigma® (Italy). Three specimens groups were considered, with a diameter in the middle cross-section ranging from 3 mm up to 12 mm. The stress field in the specimens was determined numerically and by strain gauge measurements in correspondence of the cross-section surface. The dispersion of experimental results has been accounted for, and data are reported in P-S-N diagrams. The decrease in fatigue resistance with increasing specimen size is evident. Theoretical explanation for the observed specimen-size effect is provided, based on Fractal Geometry concepts, allowing to obtain scale independent P-S*-N curves. The fatigue life expectation in the VHCF regime of the EN-AW6082 aluminium alloy full-scale components is rather overestimated if it is assessed only from standard small specimens of 3 mm in diameter. Experimental tests carried out on larger specimens, and a proper extrapolation, are required to assure safe structural design.

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Crack mode and life of Ti-6Al-4V under multiaxial low cycle fatigue

Frattura ed Integrità Strutturale ◽

10.3221/igf-esis.34.54 ◽

2015 ◽

Author(s):

Takamoto Itoh ◽

Masao Sakane ◽

Takahiro Morishita ◽

Hiroshi Nakamura ◽

Masahiro Takanashi

Keyword(s):

Hollow Cylinder ◽

Stress Ratio ◽

Biaxial Loading ◽

Fatigue Testing ◽

Low Cycle Fatigue ◽

Testing Machine ◽

Multiaxial Fatigue ◽

Cycle Fatigue ◽

Loading Test ◽

Failure Life

This paper studies multiaxial low cycle fatigue crack mode and failure life of Ti-6Al-4V. Stress controlled fatigue tests were carried out using a hollow cylinder specimen under multiaxial loadings of ?=0, 0.4, 0.5 and 1 of which stress ratio R=0 at room temperature. ? is a principal stress ratio and is defined as ?=sigmaII/sigmaI, where sigmaI and sigmaII are principal stresses of which absolute values take the largest and middle ones, respectively. Here, the test at ?=0 is a uniaxial loading test and that at ?=1 an equi-biaxial loading test. A testing machine employed is a newly developed multiaxial fatigue testing machine which can apply push-pull and reversed torsion loadings with inner pressure onto the hollow cylinder specimen. Based on the obtained results, this study discusses evaluation of the biaxial low cycle fatigue life and crack mode. Failure life is reduced with increasing ? induced by cyclic ratcheting. The crack mode is affected by the surface condition of cut-machining and the failure life depends on the crack mode in the multiaxial loading largely.

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