Beryllium improves the way we live and work and is widely found in products used throughout society. Beryllium is a naturally occurring element that is one-third lighter than aluminium, yet has six times the specific stiffness of steel. Beryllium is the fourth element on the Periodic Table with the symbol “Be”.
While it is still unknown to many, this metal imparts remarkable physical and performance qualities to its end-use products making for a better, more connected and safer world.
BACKGROUND
The primary forms of beryllium produced and used commercially are:
Metallic beryllium and alloys containing >30% beryllium
Copper beryllium alloys containing 0.10 – 2.0% beryllium
Al, Cu and Ni master/casting alloys containing 1 – 15% beryllium
Beryllium oxide ceramics
PROPERTIES OF BERYLLIUM
Beryllium Metal and Aluminium Beryllium Alloys Containing > 50% Beryllium
Beryllium is notable among metals in terms of specific rigidity; i.e. the ratio of modulus to density. The rigidity of beryllium is about 50% greater than that of steel, while its density (1.84 g/cm³) is about 30% less than that of aluminium. The specific rigidity of beryllium is around six times greater than that of any other metal or alloy. This is an extremely useful property for many aerospace applications where lightweight structures are required which are resistant to deformation under high stresses or high temperatures. It is also a highly desirable property for other applications that are subject to rapid acceleration and deceleration, such as navigational gyroscopes, high speed rotating mirrors and machine spindles. Beryllium remains stable at high temperatures (melting point 1284ºC) and can be used as a heat sink. There are materials that have some of the physical properties of beryllium but not the combination of properties needed for the demanding applications where beryllium is used.
Among other materials that have been used s for some less demanding applications where failure is acknowledged and acceptable are:
Alternate materials for the mechanical properties provided by beryllium:
-
Titanium, and it alloys
-
Magnesium and its alloys
-
Aluminium and its alloys
-
Carbon fiber composites
Alternate materials for the thermal properties provided by beryllium:
-
Aluminium metal matrix composites with Silicon Carbide / Boron Nitride
Alternate materials for the X-Ray Transmission properties provided
by beryllium:
-
Plastics
Alternate materials for the neutron moderation provided by beryllium:
-
No other material offers the same combinations of these properties
ALTERNATE MATERIALS
Copper Beryllium Alloys and Nickel Beryllium Alloys containing < 2% Beryllium
There are materials that have equivalent individual properties of strength, ductility, formability, machinability, electrical and thermal conductivity, fatigue resistance, resistance to loss of strength with long term exposure to heat etc. to those provided by the copper beryllium alloys and nickel beryllium alloys, however, no other alloys offer the same combinations of these properties. In all cases, there is a reduction in performance which can be significant particularly when the combination of properties is for the benefit and safety of society.
In particular, when lower strength alloys, with lower levels of ductility and formability, usually in combination with lower electrical or thermal conductivity, designers are forced to accept less sophisticated designs, larger sized & heavier components to achieve equivalent strength and reliability thereby defeating the objective of miniaturisation weight reduction, energy savings, and carbon footprint reduction.
Alternate materials for copper beryllium alloys could include:
-
Copper nickel silicon alloys
-
Copper iron alloys
-
Phosphor bronze
-
Copper titanium alloys
Alternate materials for some of the individual mechanical
and/or electrical and thermal conductivity properties provided
by Nickel beryllium alloys:
-
Nimonic©alloys
-
Kovar© alloys
Aluminium beryllium master alloys containing < 10% beryllium
There are no other materials available that produce equivalent properties to the aluminium beryllium master alloys used as additives for controlling the melting and alloying of aluminium alloys containing magnesium, and of melting magnesium alloys.
Reduction in the quantity of Beryllium used in applications is not feasible, since in practice beryllium is only used where absolutely necessary, due to its high price relative to other metals. Furthermore, the most prevalent use of beryllium occurs in copper beryllium alloys, which only contain between 0.5% – 2% beryllium.
REDUCTION
