Copper continued tinning

Accdg to Greener (Ref 7, p 22), the earliest cast cannons made of copper and tin were produced by a founder named Aran at Augsburg, Germany. They were primitive breech-loaders, built up of iron strips surrounded by iron rings — a method which continued for several centuries (See illustrations on p 22 of Ref 7)... 

PROTECTIVE COATING. A film or thin layer of metal glass of paint applied to a substrate primarily to inhibit corrosion, and secondarily for decorative purposes, Metals such as nickel, chromium, copper, and tin are electrodeposited on the base metal paints may be sprayed or brushed on. Vitreous enamel coatings are also used these require baking. Zinc coating are applied by continuous bath process in which a strip of ferrous metal is passed through molten zinc. 

The earliest Roman bronzes that have come down to us date from the fifth century b.c. and contain tin about 7 per cent, and lead from 19 to 25 per cent. This was the alloy used for casting the large coin (8 to 11 oz) of the Republic, known as the As. These ternary alloys were continued in use as coinage until 20 b.c. but from that date until two centuries later lead is seldom found in Roman coins except as an accidental impurity. The lead was no doubt added partly to increase the fusibility of the alloy and also because of its cheapness as compared with copper and tin. Roman bronze statues often contain 6 to 12 per cent of lead. Gowland states that the Japanese were accustomed to add lead to bronze, not merely for cheapness and increased fluidity but also to enable the development, under suitable treatment, of a rich brown patina J. Pliny gives a tip to the house-wife. When bronzes are cleaned,... 

The notion that metals can be transformed into one another by metamorphosis is quite alien to we moderns. However, it is important to remember that, hundreds of years ago, there was no real concept of an element and metals were commonly found in various states of purity. Alloys such as bronze (copper and tin) and pewter (lead and tin is one formulation) offered a smooth continuity of metallic properties—almost a form of stop-motion metamorphosis or transmutation. The very nature of metals—luster, malleability, and thermal conductivity— argued for a common aspect (or substance)—an essence of metallicity. And so. 

Wrought lead—calcium—tin alloys contain more tin, have higher mechanical strength, exhibit greater stabiUty, and are more creep resistant than the cast alloys. RoUed lead—calcium—tin alloy strip is used to produce automotive battery grids in a continuous process (13). Table 5 Hsts the mechanical properties of roUed lead—calcium—tin alloys, compared with lead—copper and roUed lead—antimony (6 wt %) alloys. 

Lead—copper alloys are the primary material used in the continuous extmsion of cable coverings for the electrical power cable industry in the United States. Other alloys, containing tin and arsenic as well as copper, have also been developed for cable sheathing in the United States to provide higher fatigue strength. 

With binary copper—lead, the continuous copper phase provides the primary load support while pockets of 20—50% lead supply a continuous lead surface film. Tin content of 3—5% is commonly incorporated with the lead to minimi2e corrosion. Copper—lead alloys, either cast or sintered on a steel back, provide good fatigue resistance for heavy-duty main and connecting rod bearings for auto, tmck, diesel, and aircraft engines. 

Properties of copper—tin—lead alloys are Hsted in Table 10. The members of the tin bronze alloy group are cast using the centrifugal, continuous, permanent, plaster, and sand molding methods. Leaded tin—bronze alloys have minimum tensile strengths of 234—248 MPa (34,000—36,000 psi) as cast in sand molds, whereas the minimum tensile strengths for high leaded tin—bronze alloys are 138—207 MPa (20,000—30,000). The values are based on measurement of test bars cast in sand molds. 

Electroless reactions must be autocatalytic. Some metals are autocatalytic, such as iron, in electroless nickel. The initial deposition site on other surfaces serves as a catalyst, usually palladium on noncatalytic metals or a palladium—tin mixture on dielectrics, which is a good hydrogenation catalyst (20,21). The catalyst is quickly covered by a monolayer of electroless metal film which as a fresh, continuously renewed clean metal surface continues to function as a dehydrogenation catalyst. Silver is a borderline material, being so weakly catalytic that only very thin films form unless the surface is repeatedly cataly2ed newly developed baths are truly autocatalytic (22). In contrast, electroless copper is relatively easy to maintain in an active state commercial film thicknesses vary from <0.25 to 35 p.m or more. 

Estimates of the earliest use of copper vary, but 5000 BC is not unreasonable. By about 3500 BC it was being obtained in the Middle East by charcoal reduction of its ores, and by 3000 BC the advantages of adding tin in order to produce the harder bronze was appreciated in India, Mesopotamia and Greece. This established the Bronze Age , and copper has continued to be one of man s most important metals. 

Bonded silver linings are fabricated for mild steel or copper vessels. They are soldered in situ to the walls of the vessel by means of a special tin-silver solder. The melting point of this solder is approximately 280°C, and 200°C is recommended as the maximum continuous operating temperature for linings bonded with it. Since the whole of the silver is firmly adherent to the vessel, bonded linings are suitable for operation under vacuum conditions, and provide excellent heat-transfer characteristics. 

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

Also, when tin-containing solder connections are made to copper, intermetaUic materials are formed. Those continue to grow to render weak surfaces. Again, a nickel layer between the substrate and the solder provides a solution to this problem. 

The development of new transducing materials for DNA analysis is a key issue in the current research efforts in electrochemical-based DNA analytical devices. The use of platinum, gold, indiiun-tin oxide, copper solid amalgam, mercury and other continuous conducting metal substrates has been reported [6]. However, this chapter is focused on carbon-based materials and their properties for immobihzing DNA by simple adsorption procedures. 

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