Durability and dislocation structure of nickel at high loading frequency
Special features of the behavior of polycrystalline nickel fatigue curves, differing by various degrees of purity and by the method of obtaining specimens have been investigated. Fatigue tests were carried out at resonance bending vibrations at a loading frequency of 2 kHz. It was established that fracture on fatigue curves is connected with the qualitative change of the dislocation structure character, i.e., the formation at high stress amplitudes of cellular structure. It is shown that the parameters of the experimental curves, approximated by short straight line segments reflect the structure of the dislocation structure, formed during cyclic tests and qualitatively interlinked with the linear dimensions of the structural elements.
KeywordsFatigue Nickel Line Segment Fatigue Test Cellular Structure
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