|Troshchenko, VT |
|Dopov. Nac. akad. nauk Ukr. 2018, 10:56-63|
Methods for determining the conditions for the transition from a scattered to localized fatigue damage are developed and justified, based on the analysis of regularities of the propagation of "short" and "long" cracks. Using the developed methods, the crack sizes and the number of loading cycles corresponding to the transition from a scattered to localized fatigue damage in carbon, alloyed, and austenitic steels and an aluminum alloy are determined in view of the stress level and properties of the materials studied. It is established that the dimensions of the fatigue cracks corresponding to the indicated transition at stresses above the endurance limit decrease with increasing the stresses and remain smaller than the size of cracks at the limit of endurance. It is shown that the sizes of the main cracks correlate with the value of the endurance limit of the materials studied, by decreasing with an increase in the endurance limit.
|Keywords: endurance limit, scattered and localized fatigue damages, short and long fatigue cracks, sizes of main cracks|
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