Assessment of mechanical characteristics of steel subject to cyclic loads effect on non-standard compact specimens

Abstract

It is showed by experiments that the use of compact specimens for determination of fracture work of steel that undertook cyclic deformations enables to identify metal with a number of cumulative fatigue damages. The yield limit determined in the first series of experiments was used for cycling parameters determination: 0.9 from the yield limit was set for damage accumulation in the elastoplastic stress range. At the same time an average cycle load was 8.9 kN, and an amplitude was 8.6 kN. It is demonstrated that specific fracture work increases upon the increase of compact specimens’ thickness. The tendency of specific fracture work decrease is observed upon fatigue damage accumulation. Thin specimens are particularly sensitive to damage accumulation. The results of the experiments indirectly support the hypothesis of fractional-dimensional surface layer existence.