Modelling of the behavior of hollow ZrO2 particles in plasma jet with regard to their thermal expansion

The effect of the expansion of hollow micro-spherical droplets due to their heating at their motion in a plasma jet is considered by the example of ZrO 2 . A fairly simple model is proposed, which accounts for the variation of the droplets size and shell thickness because of the thermal expansion of the gas cavity as well as their possible evaporation. The conducted computations have enabled the assessment of the scale of the variation of diameter (10–20 %) and shell thickness (up to 50 %) of ZrO 2 particles under the conditions typical of the plasma treatment of powder materials and producing the coatings. The influence of the given effect on the dynamics of particles heating and acceleration is investigated, and a comparative analysis of the behavior of hollow and dense particles in plasma jet is done.