Numerical Study to Represent Non-Isothermal Melt-Crystallization Kinetics at Laser-Powder Cladding

Abstract

The study of laser-powder cladding process subject to heat transfer, melting and crystallization kinetics has been carried out numerically and experimentally. The Kolmogorov-Avrami equation was applied to describe the kinetics of the phase transitions. Characteristic behavior of temperature and conversion fields has been analyzed. Melt pool dimensions, clad height dependences on mass feed rate, laser power and scanning velocity have been investigated. It has been demonstrated that the melt zone has the boundary distinct from the melting isotherm due to the fact that melting occurs with superheating and crystallization takes place at undercooling. The calculated melt pool depth and clad height are in a good agreement with the experimental results.

Models of recrystallization activated by a diffusion flow of impurities from a thin-film coating with a convection term at the crystal surface: exact solutions

“…The authors of [42] investigated the longitudinal lattice temperature distribution of the active region and compared the thermal properties of metal-metal and semi-insulating surfaceplasmon THz optical waveguides using a heat diffusion model. Features of crystallization kinetics at laser-powder cladding were actively investigated numerically [43][44][45]. New model of thermal behavior and solidification characteristics during laser welding of dissimilar metals was proposed in [46].…”