Fusible lead alloys

To date, the single most important commercial use of lead is in the manufacture of lead-acid storage batteries. However, for most of the twentieth century, the most important environmental source of Pb was gasoline combnstion. It is also used in alloys, such as fusible metals, antifriction metals, and solder. Lead foil is made with lead alloys. Lead is used for covering cables and as a lining for laboratory sinks, tanks, and the chambers in the lead-chamber process for the manufacture of sulfuric acid. It is used extensively in plumbing. Because it has excellent vibration-dampening characteristics, lead is often used to support heavy machinery. 

Further additions of bismuth, cadmium, and antimony to the tin-lead alloys result in the low inching or "fusible" alloys widely used as safety... 

High temperatures may be obtained also with the aid of baths of fusible metal alloys, e.g. Woods metal - 4 parts of Bi, 2 parts of Pb, 1 part of Sn and 1 part of Cu - melts at 71 °C Rose s metal - 2 of Bi, 1 of Pb and 1 of Sn - has a melting point of 94 °C a eutectic mixture of lead and tin, composed of 37 parts of Pb and 63 parts of Sn, melts at 183 °C. Metal baths should not be used at temperatures much in excess of 350 °C owing to the rapid oxidation of the alloy. They have the advantage that they do not smoke or catch fire they are, however, solid at ordinary temperature and are usually too expensive for general use. It must be remembered that flasks or thermometers immersed in the molten metal must be removed before the metal is allowed to solidify. 

Lead is soft and malleable, and possesses an excellent resistance to corrosion. It has been used for water pipework and waste disposal systems, but nowadays is replaced by other materials. A major application for lead is in the manufacture of lead-acid storage batteries which account for almost 30% of the annual world consumption of lead. Cable sheathing, soft solders, and fusible plugs in the sprinklers of fire-fighting systems are other applications of lead alloys (see Table 4.14). 

Low Melting Alloys. Lead ahoys having large amounts of bismuth, tin, cadmium, and iadium that melt at relatively low (10—183°C) temperatures are known as fusible or low melting ahoys. The specifications of many of these ahoys are Hsted ia ASTM B774-87 (7). 

Deville and Debray A process for extracting the platinum metals from their ores. The ore is heated with galena (lead sulfide ore) and litharge (lead oxide) in a reverberatory furnace. The platinum forms a fusible alloy with the metallic lead, which is also formed. Invented by H. E. St-Claire Deville and H. J. Debray. 

The common metals gold, silver, lead, copper, tin, iron, being similar from so many points of view, were from an early period considered as minerals especially closely related. Their fusibility their cooling again to the same solid condition the fact that they could be melted together to form other kinds of metal (alloys) their malleability either in the cold or at furnace heat their adaptability to so many common uses, coins, statues, jewelry, tools, etc. easily gave rise to the idea that they possessed a constitution more alike than was the case with minerals... 

Fusible Alloys. —Among the eutectic alloys, some are known as fusible alloys. Wood s alloy consists of two parts of tin, two of lead, seven or eight of bismuth, and one or two of cadmium it melts at 66°- ] i ° an alloy melting at 6o° (Lipowitz s) consists of tin four parts, lead eight parts, bismuth fifteen parts, and cadmium three parts. 

To prepare it, first melt the lead in a crucible, then add the bismuth and finally the tin, and stir well together with a piece of tobacco pipe stem. This fusible metal 1 will melt in boiling water, and a teaspoon cast from the alloy will melt if... 

What is unusual about Onion s Fusible Alloy compared to other metals Onion s Fusible Alloy contains bismuth, lead, and tin. Compare the melting points of these metals to the melting point of Onion s Fusible Alloy. 

Wood s metal. A four-component fusible alloy used largely in sprinkler systems, it melts at 70C, the composition being bismuth 50%, cadmium 10%, tin 13.3%, lead 26.7%. 

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