Preparation of Spherical Alumina Powder by RF Thermal Plasma: Numerical Simulation and Experimentation

Behavior of alumina powder particles in inductively coupled thermal plasma (ICTP) can provide theoretical reference and guidelines for improving preparation process of plasma spheroidization. In this study, the motion trajectories and heating process of alumina powder particles in ICTP were investigated by means of numerical simulation with FLUENT software. Then the plasma spheroidization experiment was carried out on the basis of simulation results, and the effect of input power, powder feeder rate and particle size distribution on alumina powder spheroidization were studied by combination of experimental and the theoretical analyses. The results show that the small particles absorb enough heat from thermal plasma and therefore be heated to completely melt. Furthermore, the particle can get more energy from plasma while the input power of system is increased or the powder feeder rate is decreased, which improve the spheroidization effect of alumina powder particles.