Controlled atmosphere reaction plasma synthesis of multicomponent ceramic powders

A four inch external diameter copper reaction synthesis tube for attachment to an air plasma spray gun has been designed and constructed. This tube enables the entire hot plasma zone to be enclosed by flowing gas. The tube is water cooled, and enables control of the reaction/melting conditions for the materials that are injected into the plasma as dry powder, slurry or solutions. A supersonic nozzle is also incorporated into the design to promote powder production. Provision for capturing the reaction products in water is made and separation gives the final ceramic powders.