Preparation of submicron-size yttria-dispersed copper powders from a mixture of yttrium and copper salts solution by ultrasonic mist pyrolysis process

Yttria-dispersed (0-10 mol. %) copper powder was synthesized by ultrasonic mist pyrolysis processes using a mixture of copper nitrate and yttrium nitrate solutions at 800 degreesC, under a reducing atmosphere of Ar-4%H-2. The XRD pattern showed that the copper metal and Y2O3 were formed. The TEM microstructure with an EDS analysis result of the synthesized powder showed the agglomerated spherical nature of the particles. The resulting powder was composed of spherical and solid-containing fine copper with a size of 200 nm surrounded with ultrafine Y2O3 particles with a size of less than 10 nm. The powder sizes increased with the Y2O3 content and have loose structure as a result of the formation of very fine-sized Y2O3 particles formed around the copper.