PLASMA ATOMIZATION

A new atomization technology was developed for the production of spherical powders and spray-formed shapes. The high enthalpy and high kinetic energy of multiple plasma jets were used to melt, superheat and atomize the raw materials. The plasma atomization process was tested for the production of Ti, Ni, Cu, Cu-Ni, and Al powders. Following optimization of the reactor and nozzle geometries, powders with an average particle size between 50 µm and 150 µm were produced. The powder recovery rate was over 95%, while the particle sphericity was excellent and contained no satellites. In some experiment, TiCI₄ was introduced into the exit nozzle and mixed with the Ar plasma forming gas. The highly reactive plasma jets were used to melt and atomize an aluminum wire, and the resulting spray was deposited onto a fixed substrate. The consolidated product was a composite of AI-TiAI₃ containing 10 % Ti. The deposit showed excellent mechanical properties.