The paper describes recent developments in modeling formation of plasma spray coatings. Specific attention is paid to the three-dimensional simulation of droplet impact and solidification under plasma spraying conditions. It is shown that the extent of maximum spread is primarily determined by the Reynolds number and, to a lesser degree, by the Weber number. Splashing and break-up is shown to be the result of solidification; fluid instabilities do not play a significant role in this regard. Finally, the effect of solidification on droplet spreading is insignificant when the ratio of Stefan number to Prandtl number is much smaller than unity.

Keywords