Beryllium copper

Striking of a smear or thin coating of alloy on rusty steel with a hammer. The glancing impact of stainless steel, mild steel, brass, copper-beryllium bronze, aluminium copper and zinc onto aluminium smears on rusty steel can initiate a thermite reaction of sufficient thermal energy to ignite flammable gas/vapour-air atmosphere or dust clouds. 

Copper and Alloys Copper and its alloys are widely used in chemical processing, particularly when heat and electrical conductivity are important factors. The thermal conductivity of copper is twice that of aluminum and 90 percent that of silver. A large number of copper alloys are available, including brasses (Cu-Zn), bronzes (Cu-Sn), cupronickels (Cu-Ni), and age-hardenable alloys such as copper beryllium (Cu-Be) and copper nickel tin (Cu-Ni-Sn). 

Aluminum and silicon bronzes are very popular in the process industries because they combine good strength with corrosion resistance. Copper-beryllium alloys offer the greatest strength and excellent corrosion resistance in seawater and are resistant to stress-corrosion cracking in hydrogen sulfide. 

For the elucidation of chemical reaction mechanisms, in-situ NMR spectroscopy is an established technique. For investigations at high pressure either sample tubes from sapphire [3] or metallic reactors [4] permitting high pressures and elevated temperatures are used. The latter represent autoclaves, typically machined from copper-beryllium or titanium-aluminum alloys. An earlier version thereof employs separate torus-shaped coils that are imbedded into these reactors permitting in-situ probing of the reactions within their interior. However, in this case certain drawbacks of this concept limit the filling factor of such NMR probes consequently, their sensitivity is relatively low, and so is their resolution. As a superior alternative, the metallic reactor itself may function as the resonator of the NMR probe, in which case no additional coils are required. In this way gas/liquid reactions or reactions within supercritical fluids can be studied... 

Castable refractories, ASTM classifications and specifications for, 27 510 Castables, 27 482 Cast alloys, 73 524 Cast copper-beryllium alloys, 3 653t,... 

Copper-beryllium alloys, 3 652-656 Copper borates, 4 282 Copper(I) bromide, molecular formula and uses, 7 1111... 

Thermal treatment. See Heat treatment copper-beryllium alloys, 3 654 nickel-beryllium alloys, 3 657-658 of macrofouling organisms, 26 150 Thermal vaporization sources, 24 727 Thermal vaporization rate, 24 725 Thermal waste treatment, 25 831-834, 843-845... 

Figure 12.20 shows the structure of the side-window circular cage type and linear focused head-on type of photomultiplier which are both preeminent in fluorescence studies. The lower cost of side-window tubes tends to favor their use for steady-state studies, whereas the ultimate performance for lifetime studies is probably at present provided by linear focused devices. In both types internal current amplification is achieved by virtue of secondary electron emission from discrete dynode stages, usually constructed of copper-beryllium (CuBe) alloy, though gallium-phosphide (GaP) first dynodes have been used to obtain higher gains. 

The best-known design of a diaphragm vacuum gauge is a barometer with an aneroid capsule as the measuring system. It contains a hermetically sealed, evacuated, thin-walled diaphragm capsule made of a copper-beryllium alloy. As the pressure drops, the capsule diaphragm expands. 

Heating the ammonium beryllium carbonate solution to 95°C causes nearly quantitative precipitation of beryllium basic carbonate [66104-24-3], Be(OH)2 2BeC03. Evolved carbon dioxide and ammonia are recovered for recycle as the strip solution. Continued heating of the beryllium basic carbonate slurry to 165°C liberates the remaining carbon dioxide and the resulting beryllium hydroxide [13327-32-7] intermediate is recovered by filtration. The hydroxide is the basic raw material for processing into beryllium metal, copper—beryllium and other alloys, and beryllia [1304-56-9] for ceramic products. Approximately 90% of the beryllium content of bertrandite is recovered by this process. 

The largest consumption of beryllium is in the form of alloys, principally the copper—beryllium series. The consumption of the pure metal has been quite cyclic in nature depending on specific governmental programs in armaments, nuclear eneigy, and space. The amount of beryllium extracted from bertrandite has ranged between 200 and 270 metric tons per year since 1986 (14). Small quantities of beryl were also processed during this period. 

The price of beryllium oxide powder was 154/kg in 1991. The beryllium content of copper—beryllium master alloy was 352/kg. Pure beryllium powder was priced at 615/kg whereas simple shapes in vacuum hot-pressed material were priced at about 685/kg in 1991. 

Assay of beryllium metal and beryllium compounds is usually accomplished by titration. The sample is dissolved in sulfuric acid. Solution pH is adjusted to 8.5 using sodium hydroxide. The beryllium hydroxide precipitate is redissolved by addition of excess sodium fluoride. Liberated hydroxide is titrated with sulfuric acid. The beryllium content of the sample is calculated from the titration volume. Standards containing known beryllium concentrations must be analyzed along with the samples, as complexation of beryllium by fluoride is not quantitative. Titration rate and hold times are critical therefore use of an automatic titrator is recommended. Other fluoride-complexing elements such as aluminum, silicon, zirconium, hafnium, uranium, thorium, and rare earth elements must be absent, or must be corrected for if present in small amounts. Copper—beryllium and nickel—beryllium alloys can be analyzed by titration if the beryllium is first separated from copper, nickel, and cobalt by ammonium hydroxide precipitation (15,16). 

Beryllium alloys are usually analyzed by optical emission or atomic absorption spectrophotometry. Low voltage spark emission spectrometry is used for the analysis of most copper—beryllium alloys. Spectral interferences, other inter-element effects, metallurgical effects, and sample inhomogeneity can degrade accuracy and precision and must be considered when constructing a method (17). 

Inductively coupled argon plasma (icp) and direct current argon plasma (dcp) atomic emission spectrometry are solution techniques that have been applied to copper—beryllium, nickel—beryllium, and aluminum—beryllium alloys, beryllium compounds, and process solutions. The internal reference method, essential in spark source emission spectrometry, is also useful in minimising drift in plasma emission spectrometry (17). Electrothermal (graphite... 

Impurities above maximum levels indicated in published specifications (42) can affect the properties of the finished casting. Silicon, for example, is normally added to many of the copper—beryllium casting alloys to promote fluidity, but excess silicon reduces ductility. Excessive zinc, tin, phosphorus,... 

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