Effect of Structure and Texture on Failure of Pipe Steel Sheets produced by TMCP

The method of orientation microscopy (EBSD) is used to study the structure and texture of low-carbon, low-alloy pipe steel sheets processed by controlled thermomechanical processing (TMCP). The temperatures of isothermal hot rolling varied. Samples cut from sheets showed a different fracture tendency during mechanical testing. The formation of cleavages (secondary cracks) during failure of steel is related to the presence of ferrite grains with orientation {001} <110> extended in the hot rolling direction. The formation of grains is a consequence of the isothermal hot rolling below the temperature

Structure and Properties of OCTG Pipe Cr–Mo Steel inTended for Operating in Sour Environment

При выполнении работы использовано оборудование ЦКП «Пластометрия».The paper presents the results of the study of microstructure, mechanical and corrosion properties of the economically alloyed Fe–Cr–Mo steel, designed for the production of OCTG to which the requirements are to provide increased strength and resistance to sulfide stress cracking (SSC) at the same time. The parameters that could be used for non-destructive testing methods developing to estimate the current state of structural elements during the operation conditions were established.Представлены результаты исследования структуры, механических, магнитных свойств экономнолегированной стали для нефтегазопромысловых труб, к которым предъявляются требования обеспечения повышенной прочности и стойкости к сульфидному растрескиванию под напряжением (СНР). Установлены параметры, которые в дальнейшем могут быть использованы при разработке методик неразрушающей диагностики состояния элементов конструкций из подобных материалов в процессе эксплуатации.Исследования выполнены в рамках работы по стипендии Президента РФ молодым ученым и аспирантам СП-150.2018.1

Laboratory criteria of crack resistance of high-strength steels for gas main pipelines

Low-carbon ferrite-bainite pipe steels of the K65 (Kh80) strength grade produced by two manufacturing companies have been studied using different mechanical tests and fractographic analysis of fractured surfaces. The results demonstrate that the energy capacity a (a c) and the true relative reduction at fracture φ f upon tensile tests, as well as the level of KCV -40 ≥ 250 J/cm 2 and the relative width of the zone of homogeneous ductile fracture L C/B at the fracture surface of Charpy samples upon impact bending tests, can be used as the laboratory criteria of crack resistance. © Pleiades Publishing, Ltd., 2012