Method for densification and spheroidization of solid and solution precursor droplets of materials using microwave generated plasma processing

摘要

A method for processing feed material to produce dense and spheroidal products is described. The feed material is comprised of powder particles from the spray-drying technique or solution precursor droplets from ceramic or metallic materials. The feed material is processed using plasma generated from a microwave. The microwave plasma torch employed is capable of generating laminar flow during processing which allows for the production of spheroidal particles with a homogenous materials distribution. This results in products having improved thermal properties, improved corrosion and wear resistance and a higher tolerance to interface stresses.

主权项

1. A method of producing spheroidal and dense powder product particles extracted from plasma exhaust gas following injection of feed materials consisting of powder particles or solution precursor droplets using a microwave plasma and which method comprises:
introducing axially feed material through a materials feeder into an axisymmetric microwave plasma torch; entraining said feed material using an axis-symmetric laminar entrainment flow; guiding said feed material towards the microwave plasma using an axis-symmetric laminar cooling flow; processing said feed material by exposing it to high temperature profile within the microwave generated plasma; filtering said exhaust gas of said microwave generated plasma; and extracting powder product particles from said filtered exhaust gas.