On differences in mechanisms of metal fracture in conditions of low-cycle and high-cycle fatigue

• Дата: 2014
• Автори: Мацевитый, В. М., Вакуленко, К. В., Казак, И. Б.
• Формат: Стаття
• Мова: Russian
• Опубліковано: Інститут енергетичних машин і систем ім. А. М. Підгорного Національної академії наук України 2014
• Теми: low-cycle fatigue; high-cycle fatigue; intercrystalline fracture; intracrystalline fracture; submicrocracks; damage accumulation; coercive force; УДК; 537.624.8; 539.388.1; 539.422.24
• Онлайн доступ: https://journals.uran.ua/jme/article/view/27182
• Назва журналу: Journal of Mechanical Engineering

Differences in mechanisms of damage accumulation for low-cycle and high-cycle fatigue in terms of efficiency of use of the coercive force method in diagnostics of presence of defects in metal under cyclic loading are considered.It is pointed out that, depending on level of loading amplitude, different kinds of fracture are dominant with different probability.In case of low loading amplitudes, the most probable mechanism comprises an intracrystalline fracture.In case of cyclic loading with high amplitudes, there is a high probability of fracture along crystal boundaries, which causes accumulation of more coarse fracture elements and leads to greater nonuniformity of metal. Therefore energy consumption required for shifting the domain boundaries during remagnetization is increased. A substantial change in coercive force as one of the most important characteristics of the hysteretic loop, which area represents energy consumption for metal remagnetization, results from more coarse change of magnetic structure.It is concluded that a high sensitivity of the coercive force method to development of low-cycle fatigue and far lesser sensitivity to high-cycle fatigue is connected with the said differences in metal fracture.