Powder Metallurgy
Description:
Checon’s AgCdO (SKO-B) is produced by mechanically blending silver and cadmium oxide powders and subsequently compacting these powders into strips. The solderable fine silver backing is applied as powder prior to compaction and is thus an integral part of the contact material. This manufacturing process allows the addition of precise amounts of additives and dopants to modify and adapt mechanical and electrical behavior. Checon utilizes state of the art powder handling procedures in order to maintain compliance with the strict environmental requirements. Refer to Checon’s specification sheet for details.
Checon’s AgSnO2 (GTi-10 and GTi-12) is produced by compacting co-precipitated silver tin oxide powder into a billet for subsequent extruding. Dopants are introduced during the precipitation process ensuring complete dispersion. Fine silver is then applied to produce a solderable backing integral with the material. GTi materials have been developed to display superior ductility over other AgSnO2 materials in the market ; as well as to facilitate the use of Toplay manufacturing; the superior contact attachment method. Refer to Checon’s specification sheet for details.
Checon’s AgNi (GNi-10) is mechanically blended and compacted into a billet for extrusion. GNi can be directly welded or brazed, so no silver backing layer is required. Refer to Checon’s specification sheet for details.
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Cross Section at 20x
Electrical Characteristics and Applications:
AgCdO has a lower welding tendency than equivalent silver/cadmium materials produced by wrought internal oxidation techniques. Arc erosion is somewhat higher than internally oxidized materials, particularly in devices with low magnetic blow fields. Arc mobility and arc quenching properties are excellent. AgCdO has long been the material of choice for applications from 20A through 500A due to it’s excellent anti-welding and long life characteristics.
AgSnO2 was introduced as a replacement for AgCdO as more and more companies move towards Cadmium free materials. AgSnO2 with appropriate dopants to reduce the buildup of non conductive oxide layers on the contact surface is the material of choice. Checon’s primary dopant is Bi2O3. GTi materials display excellent weld resistance as well as long electrical life and truly represent viable alternatives to AgCdO.
GTi materials are suitable for contactors of all sizes, relays, control switches, railway switch gear, and some circuit breakers. They are outstanding materials for use in DC applications with excellent resistance to material transfer during switching.
AgNi – displays moderate resistance to welding and excellent mechanical endurance making the material particularly useful in moderate duty switches and relays up to 30A. The ability to attach the material to a substrate without the need for a solderable backing layer allows intense automation of assembly and therefore a cost competitive assembly.
