In the fully heat treated and cold worked condition beryllium-copper is the hardest (HV 100-420) and strongest (tensile strength 410-1400 N/mm2) of any copper alloy.
It is similar in mechanical properties to many high strength steels but, compared to steels, it has better corrosion resistance (approximately equivalent to nickel silvers), higher electrical conductivity (16-65% IACS) and higher thermal conductivity (210W/moC). It is also non-sparking and non-magnetic. Beryllium-copper should only be specified where its unique combination of properties can be fully exploited.
Beryllium-copper has long been used for non-sparking tools in the mining, gas and petrochemical industries.
Because of the excellent fatigue resistance, beryllium-copper is widely used for springs, pressure responsive diaphragms, flexible bellows, connectors, contacts and relays, which are all subject to cyclical loading.
The anti-galling, strength and good corrosion resistance led to the widespread use of beryllium-copper for down-hole drilling tools for the oil and gas industry.
Smaller component size has become the main design criterion in the telecommunications and computer electronics markets. Companies are constantly looking for ways to reduce the size and weight of their products, such as mobile phones, iPads, tablets and lap-tops, without sacrificing performance. The unique combination of strength, electrical and thermal conductivity of beryllium-copper make it an ideal choice for miniaturised components in the above applications.
The main product forms for beryllium-copper are sheet, strip, wire, rod, tube and forgings. Castings are available.
Health and Safety
The inhalation of beryllium in a finely divided form can cause a serious lung condition in some individuals. Precautions must therefore be taken in melting, casting, machining and welding of beryllium-copper. However, in service beryllium-copper is perfectly safe to handle and use.
Photo courtesy of Brush Wellman Inc.