Reconsidering the Role of Fatigue Irregular Testing in Scientific Conclusions About the Fatigue Limit

We propose using the irregular loading fatigue testing to study the crucial topics of the subject, for instance, concerning the fatigue limit. This characteristic is important to know (1) for test accelerating; (2) To guarantee stable, reliable service. Comparative studies under block and random loading present an opportunity to draw conclusions without the ultra-sound frequencies loading, which are at some extend controversial. We present an example of proposed method application. The second stage of fatigue – namely, the crack propagation stage, is also considered (in reference). There the main idea is similar – the irregular testing provides an opportunity to judge about the maxim among the small amplitudes, which are not harmful. Direct experimental estimation of true fatigue limit requires the testing under ultra-sound frequencies, which is not under the questions nowadays.