<b>Production and Electrode Properties of Silver Powders by High-Pressure Water Atomization under Nitrogen Atmosphere</b>

Abstract

Silver powder was produced through water atomization at the high pressure of 80 MPa. Before the water atomization, silver was melted at 1330°C under nitrogen atmosphere. Scanning electron microscope observation showed that the as-prepared silver powder had various particles with morphologies such as spherical, irregular and coarse. The volume average particle size (D 50 ) of as-prepared silver powder determined by laser photo-scattering method was 7.7 μm. D 50 was influenced by the condition of atomization angle and drain rate. D 50 decreased with decreasing to atomization angle and drain rate. Electron probe micro analysis revealed that the oxygen content in as-prepared silver powder was 50 ppm. The specific resistivity of silver paste decreased to 1.75 × 10 −8 Ω·m with increasing the sintering temperature. When silver paste was sintered at 900°C for 10 min, the microstructure of silver paste was densified with the large grain growth.