The effect of parameters of hot rolling and controlled cooling on formation of the martensite-austenite component of bainitic and ferritic-bainitic structures in a pipe steel of strength class K60 is studied. The Pocket Jaw module of a Gleeble 3800 facility is used to reproduce the modes of rolling and controlled cooling of the steel. The deformed samples are subjected to an x-ray diffraction analysis. The content of untransformed austenite and martensite in the structure of the steel is determined. It is shown that the volume fraction of the martensite-austenite component varies from 0.5 to 8% depending on the studied parameters of the thermomechanical treatment. The accumulated strain is found to play the dominant role in formation of the martensite-austenite particles and to determine the fraction of acicular ferrite.

研究了热轧和控冷参数对K60强度管钢中贝氏体和铁素体-贝氏体组织的马氏体-奥氏体组分形成的影响。Gleeble 3800 设备的 Pocket Jaw 模块用于再现钢的轧制和受控冷却模式。对变形的样品进行 X 射线衍射分析。测定钢组织中未相变奥氏体和马氏体的含量。结果表明，根据热机械处理的研究参数，马氏体-奥氏体组分的体积分数在 0.5% 到 8% 之间变化。发现累积应变在马氏体-奥氏体颗粒的形成和确定针状铁素体的比例中起主要作用。