ON INTERACTION BETWEEN MATERIAL STRENGTH AND THE STRENGTH OF STRUCTURAL ELEMENTS
Based on the analysis of previously obtained experimental data, the authors of the article developed a new methodology for the assessment of structural steels ability to resist embrittling effect of stress concentrators (SC), which manifests itself in the form of loss of the bearing capacity σNF samples with an annular notch. The concept of a reserve of metal strength (break resistance Br), performs the function of “clearing” local peak surges in SC zone, blocking a possible reduction in the strength of the product. The critical values of break resistance Brb ≈ 1,6…2,2 on specimens with notch for steels with different levels of strength in the range σ0,2 ≈ 300...1500 MPa. It is proposed to use the concept of structural alloy suitability for products containing SC with a known exponent Brb. The criterion of suitability is the structural condition of Br ≥ Brb. A characteristic feature of the alloy structural suitability for products with the SC is a monotonic increase in the structural strength of the product (σNF) with increasing strength of the metal σ0,2, indicating the absence of the threat of embrittlement of the products available from the SC.