Simulation of motion and heating processes particles of Stellite 190 powder during plasma surfacing

The work simulates the processes of movement and heating of particles of Stellite 190 hard alloy powder during plasma surfacing. An analysis was carried out of the change in particle speed and the time spent in the arc plasma as they move from the plasma torch nozzle to the surfacing zone on the workpiece, taking into account both the size of the spherical particles and the flow rate of the supplied powder. It is shown that a decrease in the speed of particles occurs not only with an increase in their diameter, which causes an increase in drag in the gas flow, but also with an increase in the consumption of deposited powder due to a decrease in the average speed of the gas-powder flow at the exit from the plasmatron nozzle. It has been established that when the particle size and powder consumption change, their size has the greatest influence on the heating process and the melting time of the particles than the powder consumption. It has been shown that particles smaller than 80 microns can completely melt during their movement to the workpiece, while larger particles will melt mainly in the melting bath.