The invention relates to the technical field of
cobalt-based
powder material preparation, in particular to a preparation method of superfine spherical
cobalt powder. The method comprises the followingsteps that (1), a
cobalt salt solution reacts with an
ammonium bicarbonate or
sodium carbonate precipitant under a heating condition to obtain cobalt
carbonate precipitate; (2), the cobalt carbonateprecipitate is filtered, washed with pure water, and dried to obtain cobalt
carbonate powder; (3), the cobalt carbonate powder is placed into a calcining furnace, and heated and decomposed in an
oxygen-
free state to obtain cobaltous
oxide; (4), the cobalt
monoxide powder obtained by calcining and decomposing is placed into a reduction furnace, and
hydrogen is introduced for reduction to obtain a loose spongy cobalt block; and (5),
airflow milling is carried out on the spongy cobalt block in a closed cycle
inert gas protective
atmosphere to obtain the ultrafine spherical cobalt powder with theFisher particle size being 0.4-0.8
micrometer. The particle size of the prepared cobalt powder reaches the ultrafine grade, the cobalt powder is spherical, and the cobalt powder has the advantages ofbeing uniform and controllable in particle size, uniform in
particle size distribution, good in flowing property and the like.