Bismuth-copper alloy

Betts Electrolytic Process. The Betts process starts with lead bullion, which may carry tin, silver, gold, bismuth, copper, antimony, arsenic, selenium, teUurium, and other impurities, but should contain at least 90% lead (6,7). If more than 0.01% tin is present, it is usually removed from the bullion first by means of a tin-drossing operation (see Tin AND TIN ALLOYS, detinning). The lead bullion is cast as plates or anodes, and numerous anodes are set in parallel in each electrolytic ceU. Between the anodes, thin sheets of pure lead are hung from conductor bars to form the cathodes. Several ceUs are connected in series. 

In a similar determination described by Lingane and Jones,11 an alloy containing copper, bismuth, lead, and tin is dissolved in hydrochloric acid as described above, and then 100 mL of sodium tartrate solution (0.1 M) is added, followed by sufficient sodium hydroxide solution (5M) to adjust the pH to 5.0. After the addition of hydrazinium chloride (4 g), the solution is warmed to 70 °C and then electrolysed. Copper is deposited at —0.3 volt, and then sequentially, bismuth at —0.4 volt, and lead at —0.6 volt all cathode potentials quoted are vs the S.C.E. After deposition of the lead, the solution is acidified with hydrochloric acid and the tin then deposited at a cathode potential of — 0.65 volt vs the S.C.E. 

Controlled potential at the cathode - continued D. of bismuth, copper, lead and tin in an alloy, 518... 

In former times, tin was used widely as a constituent of metal alloys, of which bronze, solder, and pewter are common examples. Bronze is an alloy of copper containing approximately 20% tin and smaller amounts of zinc. Pewter is another Cu-Sn alloy that contains tin as the major component ( 85%), with roughly equal portions of copper, bismuth, and antimony. Solder consists of 67% lead and 33% tin. 

Traces of arsenic may occur in many metals, e.g. antimony, bismuth, copper, iron, lead, nickel, tin and zinc, and in alloys derived from such metals. Its presence generally results from the use of arseniferous ores and inadequate purification of the metals. It is found as an impurity in many dyes and colouring matters, and some arsenic compounds... 

PMS liquids are corrosion-inert substances. Under normal conditions and heated to 100-150 °C they do not cause corrosion and for a long period of time do not change in airflow when in contact with aluminum and magnesium alloys, bronzes, carbon and doped steels, as well as titanium alloys. PMS liquids do not change their properties under 100 °C in air for 200 hours in contact with the above-listed alloys as well as with beryllium, bismuth, cadmium, Invar alloy, brass, copper, mel-chior, solder, lead, silver. The stability of the properties of PMS liquids in these conditions is usually accompanied by the absence of metal and alloy corrosion, although the colour of the metal surface may slightly change. 

Silver alloys present similar problems and the silver content can be determined after dissolution of 5—10 mg in 1 ml of 50% nitric acid. The tin and gold present will appear as a black residue which may be taken up in 1.5 ml concentrated hydrochloric acid, which of course precipitates silver chloride. The precipitate is removed by centrifugation. Thus again two solvents are required to determine the normal range of elements, e.g. bismuth, copper, gold, lead, silver and tin. 

During the seventeenth century the nature of zinc was misunderstood it was frequently confused with bismuth. In 1695 Homberg identified it as the metal in blende and about 1700 Johann Kunckel von Lftwenstein recognised that calamine contains a metal that alloys with copper in the manufacture of brass. It may be recalled that both Homberg and Kunckel played an important rdle in the discovery of phosphorus (p. 76). Percy states that Henckel was the first person in Europe to make metallic zinc from... 

Another method of bonding involved the use of special metal alloys which were capable of reacting with and combining with sulphur. The earliest patent for the use of alloys was in Germany in 1904 [10]. Daft patented alloys containing antimony in the US between 1912 and 1913 [11, 12, 13, 14]. He also claimed the use of alloys of copper and zinc with bismuth and arsenic. These alloys were electrically deposited on the metal and the bonds to rubber were formed during the vulcanisation process. 

Determine the number of components in the following systems (a) an iceberg of pure HjO (b) bronze, an alloy of copper and tin (c) Wood s metal, an alloy of bismuth, lead, tin, and cadmium (it is used in sprinkler systems for fire control) (d) vodka, a mixture of water and ethyl alcohol (e) a mixture of sand and sugar. 

Crude lead contains traces of a number of metals. The desilvering of lead is considered later under silver (Chapter 14). Other metallic impurities are removed by remelting under controlled conditions when arsenic and antimony form a scum of lead(II) arsenate and antimonate on the surface while copper forms an infusible alloy which also takes up any sulphur, and also appears on the surface. The removal of bismuth, a valuable by-product, from lead is accomplished by making the crude lead the anode in an electrolytic bath consisting of a solution of lead in fluorosilicic acid. Gelatin is added so that a smooth coherent deposit of lead is obtained on the pure lead cathode when the current is passed. The impurities here (i.e. all other metals) form a sludge in the electrolytic bath and are not deposited on the cathode. 

Rubidium metal alloys with the other alkaU metals, the alkaline-earth metals, antimony, bismuth, gold, and mercury. Rubidium forms double haUde salts with antimony, bismuth, cadmium, cobalt, copper, iron, lead, manganese, mercury, nickel, thorium, and 2iac. These complexes are generally water iasoluble and not hygroscopic. The soluble mbidium compounds are acetate, bromide, carbonate, chloride, chromate, fluoride, formate, hydroxide, iodide. 

The washed slime is dried and melted to produce slag and metal. The slag is usually purified by selective reduction and smelted to produce antimonial lead. The metal is treated ia the molten state by selective oxidation for the removal of arsenic, antimony, and some of the lead. It is then transferred to a cupel furnace, where the oxidation is continued until only the silver—gold alloy (dorn) remains. The bismuth-rich cupel slags are cmshed, mixed with a small amount of sulfur, and reduced with carbon to a copper matte and impure bismuth metal the latter is transferred to the bismuth refining plant. 

Low resistance-high kA alloy (high melting point) copper-bismuth has a good resistance to cold... 

Of the elements commonly found in lead alloys, zinc and bismuth aggravate corrosion in most circumstances, while additions of copper, tellurium, antimony, nickel, silver, tin, arsenic and calcium may reduce corrosion resistance only slightly, or even improve it depending on the service conditions. Alloying elements that are of increasing importance are calcium especially in maintenance-free battery alloys and selenium, or sulphur combined with copper as nucleants in low antimony battery alloys. Other elements of interest are indium in anodesaluminium in batteries and selenium in chemical lead as a grain refiner ". 

Alloy samples weighing either 100 or 25 g. were prepared by melting weighed amounts of lead and thallium together. The c. p. granular test lead, free from silver, gold and bismuth (Fisher Scientific Company), was indicated by spectroscopic examination to contain approximately 0-005 % iron, 0-001 % thallium and 0-001 % copper. The thallium used was supplied by the Varlacoid Company. Spectroscopic examination showed the presence of approximately 0-01 % lead, 0-005 % iron, and 0-001 % copper. 

In substitutional metallic solid solutions and in liquid alloys the experimental data have been described by Epstein and Paskin (1967) in terms of a predominant frictional force which leads to the accumulation of one species towards the anode. The relative movement of metallic ion cores in an alloy phase is related to the scattering cross-section for the conduction electrons, which in turn can be correlated with the relative resistance of the pure metals. Thus iron, which has a higher specific resistance than copper, will accumulate towards the anode in a Cu-Fe alloy. Similarly in a germanium-lithium alloy, the solute lithium atoms accumulate towards the cathode. In liquid alloys the same qualitative effect is observed, thus magnesium accumulates near the cathode in solution in bismuth, while uranium, which is in a higher Group of the Periodic Table than bismuth, accumulated near the anode in the same solvent. 

Antimony alloys have many commercial applications. The metal makes its alloys hard and stiff and imparts resistance to corrosion. Such alloys are used in battery grids and parts, tank linings, pipes and pumps. The lead plates in the lead storage batteries constitute 94% lead and 6% antimony. Babbit metal, an alloy of antimony, tin, and copper is used to make antifriction machine bearings. Alloys made from very high purity grade antimony with indium, gallium and bismuth are used as infrared detectors, diodes, hall effect devices and thermoelectric coolers. 

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