Telephone
01767 604704

Nickel Silver Alloys

Nickel silver alloys (sometimes called German silver) derive their name from their bright silvery appearance though they actually contain no silver at all. They are alloys of copper, nickel and zinc and they find many applications in housewares (such as cutlery) as well as some industrial applications (such as component manufacture).

The Basics
Nickel silver alloys contain 10-25% nickel and 17-40% zinc with the remainder being copper. They are usually classified by their nickel content with higher nickel contents producing a whiter, silvery colour.

Corrosion resistance increases with higher nickel content and the resulting alloys are less vulnerable to stress corrosion than some brass alloys. Strength also increases with nickel content but the increased nickel has little effect on ductility.

For industrial applications there is limited advantage in exceeding a nickel content of 18%, however for decorative applications a higher nickel content will provide maximum resistance to stain and tarnish.

The spring properties of the alloys are good and remain so at elevated temperatures. This makes nickel silver well suited to a number of specific applications where this is a requirement.

The electrical conductivity of nickel silver is much less than that for copper.

Where a nickel silver alloy is to be machined, lead can be added to the alloy (usually 1-2%) to improve results. However, this will reduce the cold workability of the alloy

Applications
Nickel silver alloys find many applications where a decorative appearance is required e.g. housewares and giftware. They are also sometimes used as a metal substrate for silver-plated (or electroplated) goods because even if the silver plating wears off, the nickel silver underneath will still provide an attractive appearance. Sometimes this material will be referred to as EPNS (electroplated nickel silver).

In industrial applications, nickel silver alloys are often used where a combination of good strength and corrosion resistance is required. They also find applications that take advantage of the materialís springing properties. One such application is in spring contacts for the telecommunication industry.

With lead added to the alloy, the improved machinability makes it especially suitable for engraving.

Alloy selection

CW401 (NS103)
CW402 (NS101)