Beryllium alloys

(metallurgy) Any dilute alloy of base metals containing a few percent of beryllium in a precipitation-hardening system.

Dilute alloys of base metals which contain a few percent of beryllium in a precipitation-hardening system. Although beryllium has some solid solubility in copper, silver, gold, nickel, cobalt, platinum, palladium, and iron and forms precipitation-hardening alloys with these metals, the copper-beryllium system and, to a considerably lesser degree, the nickel-beryllium alloys are the only ones used commercially. See also Beryllium.

In addition to these precipitation-hardening systems, small amounts of beryllium are used in alloys of the dispersion type wherein there is little solid solubility (Al and Mg). Various amounts of beryllium combine with most elements to form intermetallic compounds. Development of beryllium-rich alloys has been chiefly confined to the ductile matrix Be-Al, Be-Cu solid solution alloy with up to 4% Cu, and dispersed-phase-type alloys having relatively small amounts of compounds (0.25–6%), chiefly as BeO or intermetallics, for dimensional stability, elevated temperature strength, and elastic limit control. See also Alloy.

Primary applications of beryllium-copper alloys are found in the electronics, automotive, appliance, instrument, and temperature-control industries for electric current–carrying springs, diaphragms, electrical switch blades, and other devices. Applications in structural aerospace and nuclear fields are submarine repeater cable housings for transoceanic cable systems, wind tunnel throats, liners for magnetohydrodynamic generators for gas ionization, and scavenger tanks for propane-Freon bubble chambers in high-energy physics research.

Beryllium intermetallic compounds (beryllides) have high strength at high temperature, good thermal conductivity, high specific heat, and good oxidation resistance. Beryllides are formed with actinide and rare metals, as well as with the transition metals. They are of interest to the nuclear field, to power generation, and to aerospace applications. Evaluation of the intermetallics as refractory coatings, reactor hardware, fuel elements, turbine buckets, and high-temperature bearings has been carried out.