Modeling of crystallization in a metal surface layer modified by nanoparticles under pulsed induction heating

Crystallization processes in the case of modification of the surface layer of an iron-based alloy (Fe–C) subjected to a pulse action of a high-frequency electromagnetic field for substrate heating and melting are numerically simulated. The processes of heating, melting, and subsequent solidification of the metal are studied with the use of a mathematical model that describes thermodynamic phenomena. It is postulated that nano-sized particles with a high melting point uniformly distributed over the melt volume favor rapid crystallization during melt supercooling owing to heterogeneous nucleation. It is found that the nucleation and crystallization conditions in different areas of the melt volume are essentially different, and the maximum number of crystallization centers arise in regions where heat removal proceeds with the greatest rate. The particle size distribution in the crystalline structure in the solidified metal volume is estimated.