The invention relates to a preparation method for metallic
cobalt microspheres. The preparation method comprises the following steps that (1) a
cobalt source mother solution is prepared from
cobalt nitrate and EDTA, and
ammonium hydroxide and water are added into the solution, so that the pH value of the solution is made to be 12.4; then the solution is transferred into a reaction still, a high-purity metallic cobalt plate is added to serve as a substrate, a
hydrothermal reaction is conducted at the temperature of 90-120 DEG C, and flushing and
drying are conducted; (2) the micron-grade spherical cobaltous
hydroxide and the metallic cobalt plate are directly sent to a
muffle furnace, the rate of temperature increase is controlled to be 1-10 DEG C per minute, the final temperature is controlled to be 250-350 DEG C, and heat preservation is conducted for 3-5 hours; (3) micron-grade spherical cobaltosic
oxide which is cooled to the temperature around 200 DEG C and the metallic cobalt plate are directly sent into a reduction furnace, the air pressure is controlled to be 0.24-0.35 Mpa, the rate of temperature increase is controlled to be 10-20 DEG C per minute, the final temperature is controlled to be 600-800 DEG C, and heat preservation is conducted for 2-3 hours; and (4)
static electricity of cooled metallic cobalt microspheres is eliminated by means of an ionic fan, and then the metallic cobalt microspheres are subjected to multi-stage
airflow winnowing for eliminating large particles with the diameters being 20 [um]m or above.