Deringer-Ney - Silver Copper Alloys

Industrial/Automotive

Contact Materials

Silver Copper Alloys

Silver-copper alloys have been developed to provide the contact user with a series of materials that exhibit an increase in hardness, some resistance to sticking, reduced material transfer and lower cost. They generally retain good conductivity, but are susceptible to the formation of copper oxide. For this reason, it is necessary to employ higher contact pressures than would be used for fine silver. These materials are used in A.C. and D.C. applications and, being a ductile material, can be fabricated into all the conventional contact forms.

Coin silver (DMC-20) is an alloy of 90% silver and 10% copper. The increased hardness of this material makes it very popular in applications such as rotary switches, where mechanical wear is a factor. Coin silver retains a hig conductivity and, in some applications can replace the more expensive fine silver.

Another very popular material is DMC-51 (75% silver, 24.5% copper, .5% nickel). This material offers the contact user a very low cost silver alloy that produces excellent results in D.C. applications. When paired with DMC-91 there is less tendency of material transfer. DMC-51 is widely used in automotive applications.

The other silver copper alloys listed offer the contact user varying degrees of physical and electrical properties.

Properties of Silver Copper Alloys

Deringer Material Number	Composition % by Weight	Density T.O./cu.in.	Hardness Range R 15T Scale	Tensile Strength x 1000 PSI	Electrical Conductivity % IACS	Melting Point F
DMC-25	92.5 Ag, 7.5 Cu	5.45	65 - 81	39 - 66	88	1510
DMC-20	90 Ag, 10 Cu	5.43	70 - 83	40 - 75	88	1500
>DMC-236	72 Ag, 28 Cu	5.25	79 - 85	53 - 80	84	1437
DMC-50	50 Ag, 50 Cu	5.09	77 - 89	54 - 75	75	1607
DMC-51	75 Ag, 24.5 Cu, .5 Ni	5.30	78 - 85	45 - 80	75	1441

Note: Hardness values are for comparative purposes only and should not be used in design specifications.