Theoretical Prediction and Experimental Determination of Fatigue Life Distributions of SAE 1008 Steel Subjected to Constant Amplitude, Block and Narrow Band Random Loading

1978 ◽  
Vol 5 (3) ◽  
pp. 165-172
Author(s):  
H. A. ElMaraghy ◽  
J. N. Siddall
2011 ◽  
Vol 462-463 ◽  
pp. 634-638 ◽  
Author(s):  
R.S. Sidhu ◽  
Aidy Ali ◽  
M.R. Hassan

It is evident that most rubber components in the automotive industry are subjected to repetitive loading. Vigorous research is needed towards improving the safety and reliability of the components. The study is conducted on an automotive rubber jounce bumper with a rubber hardness of 60 IRHD. The test is conducted in displacement controlled environment under compressive load. The existing models by Kim, Harbour, Woo and Li are adopted to predict the fatigue life. The experimental results show strong similarities with the predicted models.


2010 ◽  
Vol 2 (1) ◽  
pp. 1849-1858 ◽  
Author(s):  
Jeroen Van Wittenberghe ◽  
Jan De Pauw ◽  
Patrick De Baets ◽  
Wim De Waele ◽  
Magd Abdel Wahab ◽  
...  

1975 ◽  
Vol 17 (4) ◽  
pp. 181-185 ◽  
Author(s):  
K. J. Marsh ◽  
T. Martin ◽  
J. McGregor

Fatigue tests on simple, fillet-welded, mild steel lap joints have been carried out to determine the effects of a corrosive environment and random loading. At normal testing frequencies, a brine-drip environment had no effect on the constant-amplitude fatigue strength at short endurances. At stresses less than the in-air fatigue limit, the corrosive environment was sufficient to allow crack growth at very low stress levels. In these corrosive environment tests, reducing the test frequency by a factor of 50 halved the life. The results of narrow-band random loading tests could be predicted reasonably accurately either by a fracture mechanics method or by Miner's rule.


1950 ◽  
Vol 23 (3) ◽  
pp. 576-580 ◽  
Author(s):  
Thomas G. Fox ◽  
Paul J. Flory ◽  
Robert E. Marshall

Abstract Experimental determination of the elongation at which crystallization commences in vulcanized rubber has been attempted through measurement of density changes by a hydrostatic method. The critical elongation for incipient crystallization appears to depend on the temperature, in approximate accordance with theoretical prediction. Crystallization sets in at an elongation well below that at which the stress-strain curve assumes a steep slope.


1970 ◽  
Vol 185 (1) ◽  
pp. 339-351 ◽  
Author(s):  
D. J. White ◽  
J. Lewszuk

Push-pull fatigue tests have been made in constant amplitude loading and in narrow band random loading on fillet-welded cruciforms made from 3/8 in thick mild steel plate to B.S. 1501-151 Grade 28. The test frequency was 250 Hz, mean tensile stresses of 0, 5 and 10 tonf/in2were employed and tests were extended for endurances of up to 108cycles. Curves have been fitted to the S-N results using the relationship N( S — So)α= C and on the assumption that this may be extrapolated beyond 108cycles, curves showing the effect of mean stress are given for both constant amplitude loading and narrow band random loading for endurances up to 1012cycles. Suitable factors of safety should be applied to these stresses before use in design. For endurances beyond 107cycles, an increase in tensile mean stress from 0 to 10 tonf/in2reduced the fatigue strength by about 50 per cent in both constant amplitude loading and random loading. Reasonable agreement was found at all mean stresses between the experimental random loading S-N curves and those predicted using the constant amplitude results and the Palmgren-Miner cumulative damage hypothesis.


2011 ◽  
Vol 104 ◽  
pp. 197-205 ◽  
Author(s):  
Adam Niesłony ◽  
Andrzej Kurek

The algorithm of fatigue life determination for machine elements subjected to random loading uses fatigue characteristics of the material determined under constant-amplitude loading. They are usually stress or strain characteristics as well as characteristics using the energy parameter. Their correct selection influences correctness of the obtained results related to the experimental data. The paper presents analysis of convergence of the calculated fatigue lives of some constructional materials subjected to random loading under uniaxial loading state. For calculations concerning one material the same loading state was assumed and fatigue characteristics were determined on the basis of one data set obtained under constant strain amplitude tests. Calculated fatigue lives based on different fatigue characteristics were compared and their convergences were tested. It has been proved that convergences are different depending on the material. The comparison results were presented in form of graphs.


Sign in / Sign up

Export Citation Format

Share Document