Technique for Selecting Control Decisions in Optimizing Technological Modes of Processing Iron Ore Raw Materials Using Electromagnetic Influences

Purpose of reseach. The paper considers the process of selective pre-destruction of interphase boundaries in iron ores by using magnetic-pulse treatment. When analyzing the stress-strain state and viscous fracture, the relative similarity of the fracture criteria in the main minerals of iron ores due to magnetically-striction deformation of magnetite grains. Methods.It has been established that the strength and toughness of the destruction of magnetite exceeds the analogous properties of calcite in the composition of skarn iron ores, the strength and toughness of quartz fracture exceeds the analogous properties of magnetite. A difference in the character of the destruction of skarn ores and ferruginous quartzites. The criterion for estimating the degree of softening of interphase boundaries in iron ores due to the magnetic-impulse action based on the probabilistic approach is formulated. Results.A theoretical estimate is made of the degree of selective softening of iron ores under magnetic-pulse treatment, taking into account the strength and magnetostriction properties of magnetite. The results of experiments on nanoindentation of interphase boundaries before and after magnetic-pulse processing are presented. Conclusion. By analyzing the lengths of developing microcracks under the influence of a nanoindenter, the possibility of reducing the fracture toughness after a magnetic pulse treatment of iron ore.