The analysis of the influence of metallurgical factors (yield stress and solution resistance parameter [SR] due to the content of the main alloying elements Cr, Ni and Mo) on stress corrosion cracking of steels of different classes in an aggressive NACE solution at 25 C was performed . The dependences of the critical stress , i.e. the transition stress from active corrosion to the mechanism of hydrogen embrittlement, on the yield stress value and coefficient of stress concentration are obtained . The relationship between the critical stress, the conditional yield stress and the value of high stress concentration factor is revealed. It is concluded that the loss of corrosion resistance for unalloyed steels with a yield stress below 500 MPa is due to an increase in the concentration of hydrogen during the deformation of the material in a corrosive environment.

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Проведен анализ влияния различных параметров на метаболизм теплокровных животных: млекопитающих, воробьиных птиц и человека. Для величины основного обмена получено уравнение больцмановского типа с энергией активации, величина которой совпадает с энергией ферментативного распада макроэргических P−O-связей в молекулах аденозинтрифосфорной кислоты. Получена зависимость, связывающая продолжительность жизни млекопитающих и птиц с температурой и массой тела, величиной основного обмена и константой Рубнера.

To evaluate the effect of yield stress on hydrogen embrittlement (HE) of martensitic and ferritic steels, the effect of hydrogen (H) capture by structural inhomogeneities (hydrogen traps) and the effect of plastic deformation and stress on the mechanism of stress corrosion cracking (SCC) are considered. In the presence of hydrogen, the brittle fracture of high-strength martensitic steels consists of flat areas of intergranular fracture at the initial austenitic grain boundaries and quasi-brittle cracks at the boundaries of martensite blocks. In low-strength steels, brittle fracture manifests itself in the form of transgranular fracture of ferrite grains. The decrease in the characteristics of martensitic steels with an increase in the yield strength occurs due to an increase in the hydrogen concentration at the stage of anodic dissolution (AD) due to the growth of the carbide/matrix interface. The reason for the growth hydrogen concentration in ferritic steels is a large mechanical overstress, an increase in the number of active dissolution centers, the formation of an electrochemical pearlite-ferrite pair, and an increase in surface roughness with increasing deformation. It is concluded that the bell-shaped dependences of the critical stress of the transition from AD to SCC and other characteristics of mechanical tests on magnitude are due to different mechanisms of hydrogen accumulation in martensitic and ferritic steels.