Zone of compromise quality criteria of ST6 steel

Problem formulation Correction of the technological process of metal rolling is a task that requires material and time costs. In work to improve the indicators of mechanical properties of wide-use steels it is proposed to apply a method for determining the compromise region of the properties of the metal. This technique is based on finding the necessary combination of strength and plasticity indexes of steel. Object of study. The object of the research is the process of assessing the quality criteria of steel ST6. Materials and methods. Materials for research are selected steel ST6 in the state of factory delivery, which has a ferrite-perlite structure. Mechanical properties and chemical composition were studied in the whole working area of steel parameters. Results. An area of compromise between mechanical properties (В, Т, НВ and ) has been constructed, depending on their chemical composition (C, Si, Mn, Ni, S, P, Cr). The relationships with the best combination of strength and plasticity are determined by comparing the working areas of the given parameters. Conclusions. For steel ST6, using mathematical modeling, a method for determining the compromise area of mechanical properties, depending on the chemical composition, has been developed. The proposed method allows to predict the quality criteria of the investigated steel in the process of its release with minimum time and material costs.