Copper-beryllium alloy

The bellows is formed from a length of thin-walled tubing by extmsion in a die. The metals used in the constmction of the bellows must be ductile enough for reasonably easy fabrication and have a high resistance to fatigue failure. Materials commonly used are brass, bronze, beryllium copper, alloys of nickel and copper, steel, and Monel (5). 

Table 4. Physical Properties of Cast and Wrought Beryllium Copper Alloys...

UNS C 81500 (chromium—copper alloy) is used structurally where strength and hardness are required and UNS C 81700 (beryllium—copper alloy) is used stmcturaEy where high strength and hardness are required. 

Table 12.1 shows that spring steel, the cheapest material listed, is adequate for this purpose, but has a worryingly small safety factor to allow for wear of the linings. Only the expensive beryllium-copper alloy, of all the metals shown, would give a significant safety factor (ctj,/ = 11.5 X 10 ). 

Beryllium is obtained by electrolytic reduction of molten beryllium chloride. The element s low density makes it useful for the construction of missiles and satellites. Beryllium is also used as windows for x-ray tubes because Be atoms have so few electrons, thin sheets of the metal are transparent to x-rays and allow the rays to escape. Beryllium is added in small amounts to copper the small Be atoms pin the Cu atoms together in an interstitial alloy that is more rigid than pure copper but still conducts electricity well. These hard, electrically conducting alloys are formed into nonsparking tools for use in oil refineries and grain elevators, where there is a risk of explosion. Beryllium-copper alloys are also used in the electronics industry to form tiny nonmagnetic parts and contacts that resist deformation and corrosion. 

Beryllium acetate, basic see Beryllium and beryllium compounds) Beryllium-aluminium alloy see Beryllium and beryllium compounds) Beryllium carbonate see Beryllium and beryllium compounds) Beryllium chloride see Beryllium and beryllium compounds) Beryllium-copper alloy see Beryllium and beryllium compounds) Beryllium-copper-cobalt alloy see Beryllium and beryllium compounds) Beryllium fluoride see Beryllium and beryllium compounds)... 

The pressed and cast formulations can also be machined afterward if required but this is carried out remotely because of the hazards involved during the machining process. Also, the tools which are used for machining purpose should be of non-sparking type viz. made of brass or beryllium-copper alloy. 

Any tools used for the explosive related work should be of soft non-ferrous metals such as brass, copper or bronze, that is, tools made of non-sparking metals. Iron and steel tools should he prohibited as they might cause sparking. Tools made of beryllium-copper alloys which are non-sparking are also recommended for this purpose. 

One attractive property of beryllium is its nonsparking quality, which makes it useful in such diverse applications as the manufacture of dental appliances and of nuclear weapons. Beryllium-copper alloys find use as components of computers, in the encasement of the first stage of nuclear weapons, in devices that require hardening such as missile ceramic nose cones, and in the space shuttle heat shield tiles. Because of the use of beryllium in dental appliances, dentists and dental appliance makers are often exposed to beryllium dust in toxic concentrations. 

Magariello, E., and Hannon, M., Bonding Beryllium Copper Alloys with High Temperature Adhesives," Adhesives Age, March 1971. 

Some of the tool materials incorporate different special metals providing improvements in heat transfer, wear resistance of mating mold halves, etc. These special metals include beryllium copper alloy, brass, aluminum, kirksite, and sintered metal. 

Beryllium-copper alloys account for much of all the beryllium produced. An alloy is made by melting and mixing two or more metals. The mixture has properties different from those of the individual metals. 

Use Structural material in space technology moderator and reflector of neutrons in nuclear reactors source of neutrons when bombarded with a-parti-cles special windows for X ray tubes in gyroscopes, computer parts, inertial guidance systems additive in solid-propellant rocket fuels beryllium-copper alloys. 

Workers in Japan have shown that ultrasound can be used in electrochemical pickling and etching and smut removal in plating a beryllium-copper alloy [98]. The plating surface of Be-Cu alloys which are used commercially as electrical connectors, need to be pretreated by anodic treatment in an acid aqueous solution. These workers have shown that the smut may be effectively removed by application of ultrasound. This leads to a more resilient finish and a thickness of 0.2—3 p coating being achieved more rapidly. 

Although it may not be valuable as a pure metal, beryllium is often mixed with other metals to form alloys that have industrial uses. One example is beryllium copper alloy, or beryllium bronze. This alloy is not only hard, but does not give off sparks when it is struck. This property makes it a useful material for electrical instruments and hammers that are used in explosive environments, such as in chemical laboratories that use hydrogen or factories that make rocket fuel. 

The first high-pressure NMR studies were performed by Benedek and Purcell in the mid nineteen-fifties. They discovered that the beryllium-copper alloy Berylco-25 is nonmagnetic and that it is very suitable for high-pressure equipment for magnetic studies. Their pressurizable NMR probe (see Fig. 4.19) was similar to designs used today, and it was used at pressures up to 1 GPa (10000 atm) to study the variation with viscosity of proton relaxation times and self-diffusion eonstants in a series of liquids. Since then a variety of systems for variable-pressure experiments have been developed. Three basic approaches have been used ... 

The aqueous beryllium sulfate is separated from the solids by counter-current decantation thickener operations. A beryllium concentrate is produced by a counter-current solvent extraction process (Maddox and Foos 1966). This concentrate is stripped of its beryllium content with aqueous ammonium carbonate. By heating to 70 °C, aluminum and iron are precipitated and then removed by filtration. Precipitation of beryllium basic carbonate occurs when the solution is heated to 95 °C. The carbonate is filtered, deionized water is added, and heating to 165 °C yields a beryllium hydroxide product which is the common input to beryllium-copper alloy, beryllium oxide ceramics, or pure beryllium metal (Table 2.1-2). 

Within beryllium production plants, most scrap beryllium is recycled and reused. However, beryllium-copper alloys that are recycled at metal reclaiming plants are purified for their copper and not beryllium. In these situations the beryllium is a contaminant and workers may be unknowingly exposed to beryllium (Cullen et al. 1987). 

The first high-pressure NMR probe was developed by Benedek and Purcell in 1954 [4]. Their probe, like many of those in use today, was constructed from beryllium-copper alloy (Berylco 25) and was used in hydrostatic pressure experiments at pressures up to 10000 bar. As research in high-pressure NMR spectroscopy progressed, a large variety of increasingly specialized probes have appeared. Thus, in 1979 de Fries and Jonas reported the first... 

Traditionally, hand excavating the item has been used. Non-sparking tools such as beryllium-copper alloy shovels and trowels should be used. Plastic or nylon shovels and trowels are better in soft earth because they do not jar the item if they touch it. Excavation techniques can vary widely. Many considerations must go into selecting the proper techniques. For example, robotic techniques may be the safest for the personnel but may not have the control necessary to unearth a badly corroded chemical shell. 

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