New approaches in thermal plasma technology*

Thermal plasmas offer unique advantages for materials processing, such as high fluxes of heat and of reactant species. Recent developments have concentrated on improving control of these fluxes across the boundaries surrounding the thermal plasma. Secondary discharges (hybrid plasma generators) and pulse modulation of the plasma have been some of the approaches for this end. The use of such methods is described for selected applications. Plasma characterization through advanced models and diagnostics are concentrating on description of plasma instabilities and various nonequilibrium conditions. Understanding of these effects will allow their use for enhanced processing methods.