EXPERIMENTAL DETERMINATION OF ENERGY FATIGUE CHARACTERISTICS OF THE ALLOY D16T (2024) FREE OSCILLATION METHOD

А. Г. Дибир, А. А. Кирпикин, Н. И. Пекельный

Abstract


In the process of studying fatigue characteristics of materials, components, assemblies and entire structures, as well as the prediction of durability, it is necessary to know the energy fatigue characteristics of various materials. These parameters include α – a fatigue failure parameter and W-1– irreversibly dissipated energy per loading cycle at stresses equal to the fatigue limit based on N = 107 cycles. The logarithmic damping decrement shows the fraction of irreversibly scattered energy when the oscillations decay from the total elastic energy of the oscillations. It has been proven that for metals fatigue failure is a constant "dangerous" energy. This paper describes the experimental determination of these energy characteristics for one of the most common materials in aviation, D16T (2024). By measuring the logarithmic damping factor in the fatigue test process, the dissipated energy is found over the loading cycle. Tests are conducted at two different loading levels. This allows to obtain a system of two equations to determine the two energy characteristics α and W-1.


Keywords


logarithmic damping decrement, scattered energy, energy fatigue characteristics

References


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DOI: https://doi.org/10.32620/oikit.2019.84.08

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