Spray conversion process for the production of nanophase composite powders

摘要

A process is described for the production of composite powders with ultrafine microstructures. The process involves three coordinated steps: 1) preparation and mixing of an appropriate starting solution; 2) spray drying to form a chemically homogeneous precursor powder; and 3) fluid bed thermochemical conversion of the precursor into the desired nanophase composite powder. Both spray drying and fluid bed conversion are scaleable technologies, and together provide the means for producing bulk quantities of nanophase composite powders at low manufacturing cost. Processing parameters are controlled to ensure maintenance of chemical and microstructural uniformity at the nanoscale (less than 0.1 micron) level. Spray conversion processing is a versatile technology, which can be applied to a variety of metal-metal (e.g. W-Cu), ceramic-metal (e.g. WC-Co), and ceramic-ceramic (e.g. Al2O3-SiO2) nanophase composite powders ceramic-metal (e.g. WC-Co), and ceramic-ceramic (e.g. Al2O3-SiO2) nanophase composite powders.