Proposition of fatigue test method and fatigue properties of concrete under varying compressive repeated load.

The core of ultrasonic accelerate fatigue test is resonance, and specimens need resonating with the system. The ultrasonic fatigue test method was used to investigate the high cycle fatigue properties of LZ20Mn2 axle pipe steel. Tests were conducted on cylindrical dog-bone specimens, and all fatigue loadings were controlled by inputting vibration amplitude. The results showed that the S-N curve of LZ20Mn2 axle pipe steel presented a slow-decline shape and subsurface crack initiation. The fatigue fracture was observed by SEM. Two different crack initiation mechanisms were observed which were the mixed inclusions and dislocation. Crack closure effect played an important role at fatigue crack propagation area and the fracture mechanism was a typical plastic fracture.

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Verification of the Fatigue Test Method Applied with the Use of Mini Specimen

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.598.243 ◽

2014 ◽

Vol 598 ◽

pp. 243-248 ◽

Cited By ~ 3

Author(s):

Tomasz Tomaszewski ◽

Janusz Sempruch

Keyword(s):

Aluminum Alloy ◽

Fatigue Test ◽

High Cycle Fatigue ◽

Fatigue Testing ◽

Construction Material ◽

Test Method ◽

Fatigue Properties ◽

Cycle Fatigue ◽

Testing Methodology ◽

Standard Specimens

In special situations the fatigue properties of the construction material can be determined using non-standard specimens, for example smaller than the normative ones (the so-called mini specimens). The research presented was made for the aluminum alloy based on the high-cycle fatigue testing methodology. The verification was made by breaking down the results with own tests which involved the use of standard specimens and stands as well as with the literature reports.

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Corrosion Fatigue Tests of Micro-Sized Specimens

MRS Proceedings ◽

10.1557/proc-657-ee5.11 ◽

2000 ◽

Vol 657 ◽

Cited By ~ 4

Author(s):

Y. Mizutani ◽

Y. Higo ◽

Y. Ichikawa ◽

A. Morita ◽

K. Takashima ◽

...

Keyword(s):

Fatigue Test ◽

Corrosion Fatigue ◽

Focused Ion Beam ◽

Ion Beam ◽

Fatigue Tests ◽

Test Method ◽

Fatigue Properties ◽

Mems Devices ◽

Problems And Solutions ◽

Beam Type

ABSTRACTCorrosion fatigue properties of micro-sized materials are extremely important to design MEMS devices and micro-machines used in corrosive environments. However, there have been few studies that investigate corrosion fatigue properties of micro-sized materials. Thus, it is necessary to develop a corrosion fatigue test method for micro-sized materials. However, there are several difficulties in corrosion fatigue tests on micro-sized specimens. It is also necessary to clarify the problems for the method and to find their solutions. In this investigation, a corrosion fatigue test method for micro-sized specimens has been developed and corrosion fatigue tests for micro-sized Ni-P amorphous alloy specimens have been carried out in a 0.9% NaCl solution. Specimens of cantilever-beam-type with dimensions of 10 × 12 × 50 μm3 were prepared from a Ni-P amorphous thin film by focused ion beam machining. Corrosion fatigue tests on the micro-sized specimens were succeeded, and environmental effects on fatigue properties of micro-sized specimens were clearly observed. Several problems and solutions for the method were described.

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