PSI - Issue 65

Prokopyev L.A. et al. / Procedia Structural Integrity 65 (2024) 170–176 Prokopyev L.A., , Andreev Ya.M., Semenov S.O., Lukin E.S. / Structural Integrity Procedia 00 (2024) 000–000

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with trim size 192 x 262 mm. Do not number pages on the front, as page numbers will be added separately for the preprints and the Proceedings. Leave a line clear between paragraphs. All the required style templates are provided in the file “MS Word Template” with the appropriate name supplied, e.g. choose 1. Els1st-order-head for your first order heading text, els-abstract-text for the abstract text etc. The purpose of this work is to study the possibility of quantitatively assessing the effect of temperature on the size of the plastic zone, based on data on the yield strength of the material. In this work, we investigated one of the possible factors influencing the ductile-brittle transition: the temperature dependence of the plastic zone at the crack tip. The temperature dependence of the yield strength of the materials aluminum "5083-O", aluminum "2219-T87", steel "Cr–Mn–Ni–Mo–N steel", steel "A 107", steel "A 516-60" was used to describe the decrease the size of the plastic zone with decreasing temperature. The dependence of the yield strength of a material on temperature depends on many factors, such as the type of rolled product, technological processing mode, heat treatment mode. In accordance with the thermally activated flow model, as shown by Solntsev (2020) and Trofimov (2015) the yield strength is expressed by formula Ошибка! Источник ссылки не найден. : (1) where Ϭ Y (t) – yield strength as a function of temperature, Ϭ μ – athermal component, B, β – coefficients of the material, e – strain rate, t – temperature. As the temperature decreases, the yield strength increases significantly in the case of a constant strain rate and other equal conditions. The yield strength values at several temperature levels are taken from Junaidi (2003), Kostina (2021) and Umezawa (2021). These values are extrapolated using the least squares method, in accordance with formula Ошибка! Источник ссылки не найден. . lg( ) e ( ) t Y         t B 2. Material and methods

Fig. 1. Yield stress for several materials according to a thermally activated flow model.