The invention provides micron silver
powder for electronic paste and a preparation method of the micron silver
powder, and belongs to the technical field of
metal powder.The preparation method comprises the steps that a
silver nitrate solution, an alkaline solution and a
reducing agent solution are prepared; under a stirring state at 20-25 DEG C, dropwise adding the
silver nitrate solution into the alkaline solution to obtain a
mixed solution; under the conditions of 30-35 DEG C and
ultrasonic dispersion, a
reducing agent solution is dropwise added into the
mixed solution, and a silver
powder suspension is obtained through a reduction reaction; carrying out
solid-liquid separation on the silver
powder suspension to obtain a silver powder wet material; and performing fluid shearing cleaning on the wet silver powder, and then performing
solid-liquid separation,
drying and screening to obtain the micron silver powder for the electronic paste. According to the method, by introducing the synergistic process of gradient
temperature control,
ultrasonic dispersion,
fluid shear cleaning and the like, precise control over the morphology and purity of the silver powder is achieved, so that the micron silver powder which is soft in texture, high in purity, high in
sintering activity and excellent in
slurry applicability is prepared, meanwhile, the
process conditions are mild, and large-scale production is easy to achieve.