Production and characterization of silver powder created using high-pressure water atomization

Abstract

Silver powders are important for the production of silicon solar cells and low-temperature co-fired ceramics. In this study, a silver powder was produced at a rate of 2 kg/min through water atomization with a water pressure of 80 MPa and water flow rate of 220 L/min. Scanning electron microscopy analysis showed that the silver particles produced were aggregated and had various types of morphologies such as spherical, elliptical, and irregular. The volume average particle size and its standard deviation were 8 and 4.1¯m, respectively. Powder X-ray diffraction revealed that the as-prepared silver powder had a single phase with high crystallinity. The oxygen content in the silver powder measured by electron probe micro analysis was 50 ppm. The silver powder was classified to the size of¯2.5¯m, and the shrinkage of the silver paste was 25.5% at 900°C, comparable to that of the powder obtained by chemical reduction. Electrical measurements revealed that the specific resistivity of the silver paste sintered at 900°C for 60 min was 2.11 © 10 ¹8 ³ m. The silver paste exhibited lower specific resistivity when the sintering temperature was high and sintering time was long.

The silver paste containing ZnO-B2O3-SiO2 glass sintered at high temperature with low solid content formed high performance conductive thick film on MgTiO3 microwave ceramics

“…To analyze the reason for the variation in the resistivity of silver films with temperature, the surface morphologies of silver films obtained under different sintering conditions were studied. As shown in figure 8, the silver film became denser with the increase in temperature, resulting in a decrease in resistivity [39]. At a sintering temperature of 730 °C, fewer sintering necks between silver particles and smaller grain sizes were observed because, under this sintering condition, the softening degree of glass was low, the fluidity was poor, the amount of liquid phase decreased, the silver powder could not be completely wetted, and the high-quality silver network could not be formed.…”

Synthesis of copper particles covered with cobalt-catalyzed carbon nanofibers and their application to air-curable conductive paste

“…First (alloy powder atomization), Cu-Co alloy powder is prepared via water atomization. 20,21) Metal ingots (24.75 kg of Cu, 0.25 kg of Co, and nominal composition of Cu=Co = 99=1 w=w) were loaded into the crucible of the atomization equipment and heated (1400 °C) in order to melt them, and were subsequently atomized by high-pressure water. The cobalt composition of atomized powder was measured to be Co = 0.98 wt % by ICP-AES, which was close to the target value (obtained at Nippon Atomized Metal Powders).…”

Characterization of Silver Powder Produced through Water Atomization and RF Plasma Treatment

“…Water atomization apparatus [17] consisted of an atomizer nozzle, tundish and melting furnaces, a water tank, and a filter press. Silver products (99.99%) which were made using silversmithing method were used as the starting materials.…”