Numerical Simulation of Thermal Physical Processes During Surface Layer Modification in Metal Subjected to Induction Heating

We performed numerical simulation of thermal physical processes during surface layer modification in metal contained in a moving substrate. A layer of specially prepared nanoscale particles of a refractory compound coats the substrate surface. These particles penetrate the melt and then serve as active crystallisation nuclei. We investigated whether it is possible to use a high-frequency electromagnetic field to heat and melt metal in order to subsequently modify it. We employed empirical equations to describe the distribution of electromagnetic energy in the metal. We used the Stefan approximation for metal melting, and assumed that during solidification all the nanoparticles become nuclei of progressive volumetric crystallisation. Numerical simulation results allowed us to estimate the temperature field distribution, dimensions of melting and crystallisation regions, variations in the solid phase ratio in the biphase region, treated substrate surface area as a function of its movement velocity and induction heating properties. We determined that the width of the biphase region during metal solidification does not exceed 100 µm, and solidification time is several milliseconds

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