Alloy manufacture

Copper—Zinc Brasses. Copper—zinc alloys have been the most widely used copper alloy during the 1990s. It is no accident that the word brass is included in the name of many copper alloy manufacturers. The manufacture of brass buttons and other brass artifacts was the principal reason for the estabhshment of the U.S. copper alloy industry in Connecticut during the 1800s. 

Alloys based on Ag—Pd have been used for a number of years and are available from most gold alloy manufacturers (148). The palladium content is 22—50 wt % silver content is from 35 to 66 wt %. Minor amounts of Zn, In, or Sn are often present to increase fluidity. Both In and Sn form intermetaUic compounds with both Pd and Ag and, therefore, some of the commercial alloys are susceptible to age hardening (149). These alloys are somewhat difficult to fabricate and require meticulous processing. They may also produce a greenish discoloration when they are fused with porcelain veneers. Nevertheless, clinical experience generally has been satisfactory, and cost is the primary criterion for use. 

Enterline PE, Marsh GM Mortality among workers in a nickel refinery and alloy manufacturing plant in West Virginia. J Natl Cancer Inst 6S 92S-933, 1982... 

Uses. Electroplating manufacture of rhodium-platinum alloys manufacture of high-reflectivity mirrors... 

A more recent development that is attracting considerable attention is the use of lanthanum in high-temperature iron-base alloys. One such alloy manufactured in the U.S.A. (5) combines excellent oxidation resistance to llOO C with good ductility and ease of fabrication. By comparison with other alloys possessing similar mechanical properties, the manufacturers attribute the alloys superior oxidation resistance to what they describe as a small (200 ppm) but effective addition of lanthanum. 

The bulk of the concentrate separated from molybdenite ore by flotation is further processed to produce molybdenum. A typical extraction and purification procedure is outlined in Figure 2.1. The concentrate is roasted to convert the moiybdenum disulphide to molybdic oxide. The product is called roasted concentrate, and about 30% is marketed as Technical Oxide, mainly for alloy manufacture. A typical range of compositions is shown in Table 2.6. 

The purified nickel and cobalt sulfates, with low concentrations of ammonium sulfate, are reduced with hydrogen in agitated autoclaves at 375°F and 650 psig. By controlling the pH between 0.9-1.8 by continuous addition of aqueous ammonia, 95% of the Ni is preferentially reduced. The nickel powder is washed, filtered, dried, and packaged or is briquetted and sintered at 1750°F in hydrogen before shipment to alloy manufacturers. 

We also collect information on the history of specific companies, where such is available to us. The history of special industries, such as inkmaking, dental alloy manufacture, cellophane, and various other interesting specialties, is also in demand. 

Zirconium tetrachloride, ZrCU- Mol. wt. 233.05, sp. gr. 2.8, subl. above 300°. Supplier Titanium Alloy Manufacturing Co. 

Titanium Alloy Manufacturing Division, National Lead Co., 111 Broadway, New York 6, N. Y. 

Abstract Structure of Ali0o-xScx, Al9iCe9.xScx, and Al85NiioCe5.xScx alloys manufactured... 

High alloys with little exception suffer some embrittlement if exposed to sustained high-temperature service due to the formation of intermetallic compounds. Conditions and rates of embrittlement vary with the alloy. Check with alloy manufacturers for specific information. High alloys containing enough nickel to ensure an austenitic microstructure are, like austenitic stainless steels, unaffected by low-temperature embrittlement. 

Several stabilized nickel-based high alloys (such as Alloy 825 (22Cr-42Ni-3Mo, Ti stabilized) (UNS N08825) are resistant to sensitization. They are usually furnished in the stabilization annealed condition but may be made susceptible to sensitization by subsequent PWHTs. The alloy manufacturer should be consulted before undertaking stress relief or PWHTs. 

Silver-White metal or dusts. Reacts with some acids to produce flammable hydrogen gas. Exposures have occurred in nuclear and aerospace workers may be present in any specialty metal alloy manufacturing process. 

About 150,000 workers are exposed to zinc at their jobs. Jobs where people are exposed to zinc include zinc mining, smelting, and welding manufacture of brass, bronze, or other zinc-containing alloys manufacture of galvanized metals and manufacture of machine parts, rubber, paint, linoleum, oilcloths, batteries, some kinds of glass and ceramics, and dyes. People at construction jobs, automobile mechanics, and painters are also exposed to zinc. 

Li Q, Zhang GD, Blucher JT, Cornie JA, Microstructure of the interface and interfiber regions in P-55 reinforced aluminum alloys manufactured by pressure infiltration, Ishida H, ed.. Controlled Interphases in Composite Materials, Elsevier, New York, 131, 1990. 

Little information is available concerning metal release from surgical implants and dental alloys. Manufacturers of these types of products should be required to present data on metal release as well as on composition. 

The operations and facilities include ore exploration (not included in NFCIS list), mining, ore processing, uranium recovery, chemical conversion to UO2, UO3, UF4, UFg, and uranium metal, isotope enrichment, reconversion of UF to UO2 (after enrichment), and fuel fabrication and assembly that are all part of the front end of the NFC. The central part of the NFC is the production of electric power in the nuclear reactor (fuel irradiation). The back end of the NFC includes facilities to deal with the spent nuclear fuel (SNF) after irradiation in a reactor and the disposal of the spent fuel (SF). The spent fuel first has to be stored for some period to allow decay of the short-lived fission products and activation products and then disposed at waste management facilities without, or after, reprocessing to separate the fission products from the useful actinides (uranium and plutonium). Note the relatively large number of facilities in Table 2.1 dedicated to dealing with the spent fuel. Also listed in Table 2.1 are related industrial activities that do not involve uranium, like heavy water (D2O) production, zirconium alloy manufacturing, and fabrication of fuel assembly components. 

This metal is used in alloys, rust prevention, solders and pigments. A fume may be released during smelting, alloy manufacture or when... 

EEI has used both commercially sintered silver powder with 1-mm-thick electrodes and sintered silver powder with in-house electrodes made from an ABj-type metal-hydride alloy (also known as lanthanum-nickel alloy) using rare earth material for initial laboratory cell test evaluations. Introduction of rare earth material improves the oxidation resistance during the alloy manufacturing process. The ABj-type metal-hydride alloy should be widely used in sealed Ni-MH batteries. The use of rare earth metal lanthanum will provide improved electrical performance, enhanced reliability, and ultra-high longevity for the sealed Ni-MH and Ag-MH battery systems. 

Lifetime testing by resistance heating is used extensively by alloy manufacturers as a tool for quality control or as a screening test for alloy modification and... 

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