Mathematical modeling of powder melting process in selective laser melting technology

In this paper, the results of developing a mathematical model for the process of estimating the thermal state of spherical particles of a powder composition processed in a single mode in selective laser fusion technology are given. The model takes into account: the features of transferring the energy of laser radiation to particles with their dimensions smaller than the radiation spot comparable with the diameter of the diameter; transfer of energy through the upper half of the sphere with the dependence of the absorption coefficient of radiation on the angle of its fall; melting of material in the range of solidus and liquidus temperatures; the possibility of evaporation of the surface material; the dependence of the thermophysical parameters of the material on temperature. The model is adapted to the form applicable for implementation in the standard finite-element software product ANSYS Transient Thermal, on which numerical simulation of the process is performed. It has been found that the size of the particle size range used by the powder composition fraction determines the choice and designation of the laser treatment mode to ensure a high quality of the material after melting.