METHOD FOR DETERMINING ENDURANCE LIMIT OF SHEET MATERIAL Russian patent published in 2021 - IPC G01N3/32 

FIELD: metallurgy.

SUBSTANCE: invention relates to a technique for strength testing of semi-finished metal materials, in particular, to a method for determining the effect of preliminary plastic deformation on the endurance limit of sheet material. Essence: from the sheet material, samples are made symmetrical with respect to the tension axis and having equal thickness, consisting of gripping, transitional and working parts, and the cross-sectional area of the working part of the samples changes linearly. The samples are preliminarily loaded with static tension until plastic deformation, variable along the length of the working part of the samples, is formed. The samples are rigidly fixed in the gripping part and fatigue tests are carried out by means of cyclic loading. Cyclic loading of the samples is carried out according to the "flat bending" scheme, the locations of the fracture sites of the samples are analyzed and a graph of the dependence of the fatigue limit σ-1 on the preliminary deformation is plotted.

EFFECT: ability to predict the resource of structural elements for all values of preliminary deformation in a given interval, with the lowest possible material consumption and labor intensity with increased data reliability.

3 cl, 4 dwg