QUALITY AND FATIGUE CHARACTERISTICS RELATION

This paper will explore the mutual correlation of fatigue characteristics ((Kath, σc, ac = f (Rm)) of five structural steels tested at highfrequency loading based on tests (f ≈ 20 kHz, T = 20 ± 10 °C, R = -1). Different fatigue resistance parameters have different meanings and misunderstanding can lead to significant quality problems in component operation. Consequently, it is necessary to completely understand the relation between the two most important fatigue characteristics which are fatigue limit σc and the threshold value of the stress intensity factor amplitude Kath and how they act with changing of steel ultimate tensile strength.