Experimental determination of the specific volume phases n the intercritical interval of temperatures by heat treatment of low carbon steel

In modern conditions the requirements for the finished products are constantly increasing, so the role of technologies that improve the mechanical properties of complex products increase as well. The article deals with one of these technologies - heating of low carbon steel in the two-phase region (а+у), followed by accelerated controlled cooling or hardening from the intercritical interval (ICI) temperatures. Methodology. Methods used: metallographic and tests of mechanical properties. To estimate was developed the real specific volume phase a method based on the detection of interphase (а-у) boundaries using metallographic microscope reflected light. Purpose - search for patterns of structure formation and properties of rolled low carbon steel depending on the heating temperature in the region of intercritical interval and subsequent cooling. Findings. Experimental data on the amount of austenite involved in the formation of high-strength components of the structure of low-carbon steels. Temperature treatment regimes proposed were promoting grain size refinement and increase toughness of steel. Originality. A method to identify the former austenite grain boundaries in the structure of low carbon steels using light metallographic microscope was developed. With this method it is possible to control the proportion of phases on the slices and determine the position of interphase boundaries by heat treatment of low-carbon steels by heating to temperatures of ICI. Practical value. A new rolling pattern in ICI with accelerated cooling of steel sheets 10G2FB was proposed.