Changes

after 50% cold working

The high Cu content alloy materials are closest in their properties to pure copper materials. By defined addition of small amounts of alloying elements it is possible to increase the mechanical strength and especially the softening temperature of copper and at the same time decrease the electrical conductivity only insignificantly (Fig. 5.4). Silver, iron, tin, zinc, nickel, chromium, zirconium, silicon, and titanium are used. Usually the additive amounts are significantly below 3 wt%. This group of materials consists of mixed crystal as well as precipitation hardening alloys. The precipiytion hardening copper-beryllium and copper-chromium-zirconium materials are decribed later in a separate section.