Fabrication of Silver-Graphite Contact Materials Using Silver Nanopowders

Abstract

Silver-graphite (AgC) composites are used in electrical switchgears as arcing as well as sliding contacts. AgC composite powders for electrical contact applications are conventionally prepared using micron-size silver powder. Present investigation is aimed at exploring the effect of nanosize silver powder, made by colloidal synthesis route, on the processing and properties of AgC contact materials. The AgC composite powders synthesized from micron-size and nanosize silver powders, respectively, are characterized for particle size distribution by dynamic light scattering technique, x-ray diffraction, and scanning electron microscopy. The bulk solid compacts produced by conventional powder metallurgy process of pressing, sintering, and repressing of AgC composite powders are evaluated for their density, microhardness, electrical conductivity, and microstructure. The study reveals that the use of nanosize silver powder not only leads to reduction in sintering temperature but also contributes in improving the properties of the AgC contact materials.

Fabrication And Properties Of Silver Based Multiwall Carbon Nanotube Composite Prepared By Spark Plasma Sintering Method

“…The increase of content of multiwalled carbon nanotubes causes reduction of relative density of the sinters. The other authors [9,10] observed density in the range from 8.8 g/cm 3 to 9.45 g/cm 3 for silver based materials with addition of graphite. Low density of the produced composites results mainly from lower density of carbon nanotubes in relation to graphite.…”

Silver/reduced graphene oxide nanocomposite materials synthesized via a green molecular level mixing

“…However, it was reported that the addition of oxides lowers the thermal conductivity (TC) [1][2][3][4][5] while the presence of graphite degrades the mechanical properties. 1,[6][7][8] Therefore, the creation of multifunctional composed of nano-carbon reinforcement such as graphene (G) or reduced graphite oxide (rGO) may fulfill these unmet needs. [9][10][11][12][13][14][15] Nonetheless, the size difference between the matrix powder (i.e.…”

Effects of Different Post-Treatments on Arc Erosion Resistance of Cold-Sprayed AgC Composite Electric Contact

“…The most widely used technology for the production of contact materials is powder metallurgy. However, the sintering bulk AgC composite with the silver as matrix would consume a lot of silver, inducing high cost in an industrial scale [5,6]. Compared with powder metallurgy, the electroplating process can largely reduce the consumption of silver by using the AgC composite as coating instead of bulk.…”