Iron-copper alloys

Fis] Fischer, W.A., Janke, D., The Free Enthalpies of Reaction for the Dissolution of Oxygen in Melts of Copper-Nickel, Copper-Cobalt, and Copper-Iron Alloys (in German), Z. Metallkd., 62(10), 747-751 (1971) (Experimental, Thermodyn., Phase Relations, 5)... 

Bis] Biswas, A.K., Snow, H.P., The Thermodynamic Properties of Oxygen in Liquid Copper-Iron Alloys , Canad. Metall. Quart., 12, 257-264 (1973) (Experimental, Phase Relations, Thermodyn., 6)... 

Data on thermodynamic properties, mainly on the activity of phosphorus in liquid copper-iron alloys were... 

Iwa] Iwase, K., Okamoto, M., Amemiya, T., On the Formation of Two Liquid Layers in Copper-Iron Alloys , Sci. Rep. Tohoku Imp. Univ, 26, 618-640 (1938) (Phase Diagram, Phase Relations, Morphology, Experimental, 32)... 

The accuracy of a watch is influenced by changes in temperature. For example, an increase in temperature produces a slight increase in balance wheel diameter, which causes the wheel to oscillate more slowly and the watch to lose time. Inaccuracies may be reduced by using a low-expansion alloy, such as Invar, for the balance wheel. Most of today s high-precision watches, however, use a low-expansion beryllium-copper-iron alloy having the trade name Glucydur its antimagnetic characteristics are superior to those of Invar. 

The electrical industry is one of the greatest users of copper. Iron s alloys -- brass and bronze --are very important all American coins are copper alloys and gun metals also contain copper. 

TABLE 11.58 Type J Thermocouples Iron vs. Copper-Nickel Alloy Thermoelectric voltage in millivolts reference junction at 0°C. 

The process is used for ferrous P/M stmctural parts that have densities of at least 7.4 g/cm and mechanical properties superior than those of parts that have been only compacted and sintered. Depending on the appHcation, the porous matrix may be infiltrated only partially or almost completely. Copper-base alloy infiltrants have been developed to minimise erosion of the iron matrix. 

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. 

Iron, steel, nickel, copper—nickel alloys, and Inconel Ni—Cr—Fe are satisfactory for dry or hot sulfur dioxide, but are readily corroded below the dew... 

Corrosion. Copper-base alloys are seriously corroded by sodium thiosulfate (22) and ammonium thiosulfate [7783-18-8] (23). Corrosion rates exceed 10 kg/(m yr) at 100°C. High siUcon cast iron has reasonable corrosion resistance to thiosulfates, with a corrosion rate <4.4 kg/(m yr)) at 100°C. The preferred material of constmction for pumps, piping, reactors, and storage tanks is austenitic stainless steels such as 304, 316, or Alloy 20. The corrosion rate for stainless steels is <440 g/(m yr) at 100°C (see also Corrosion and corrosion control). 

Molten tin wets and adheres readily to clean iron, steel, copper, and copper-base alloys, and the coating is bright. It provides protection against oxidation of the coated metal and aids in subsequent fabrication because it is ductile and solderable. Tin coatings can be appHed to most metals by electro deposition (see Electroplating). 

Tin is used in various industrial appHcations as cast and wrought forms obtained by rolling, drawing, extmsion, atomizing, and casting tinplate, ie, low carbon steel sheet or strip roUed to 0.15—0.25 mm thick and thinly coated with pure tin tin coatings and tin alloy coatings appHed to fabricated articles (as opposed to sheet or strip) of steel, cast iron, copper, copper-base alloys, and aluminum tin alloys and tin compounds. 

Antimony may be added to copper-base alloys such as naval brass. Admiralty Metal, and leaded Muntz metal in amounts of 0.02—0.10% to prevent dezincification. Additions of antimony to ductile iron in an amount of 50 ppm, preferably with some cerium, can make the graphite fliUy nodular to the center of thick castings and when added to gray cast iron in the amount of 0.05%, antimony acts as a powerflil carbide stabilizer with an improvement in both the wear resistance and thermal cycling properties (26) (see Carbides). 

Uses. Copper—nickel—iron alloys, UNS C 96200 (90 10 copper nickel) and UNS C 96400 (70 30 copper nickel), are used in corrosion-resistant marine (seawater) appHcations. UNS C 96400 is used for corrosion-resistant marine elbows, flanges, valves, and pumps. Leaded nickel—brass, UNS C 97300 (12% nickel-silver), is used for hardware fittings, valves, and statuary and ornamental castings. 

Similarly, graphitically corroded cast iron (see Chap. 17) can assume a potential approximately equivalent to graphite, thus inducing galvanic corrosion of components of steel, uncorroded cast iron, and copper-based alloys. Hence, special precautions must be exercised when dealing with graphitically corroded pump impellers and pump casings (see Cautions in Chap. 17). 

Martensitic phase transformations are discussed for the last hundred years without loss of actuality. A concise definition of these structural phase transformations has been given by G.B. Olson stating that martensite is a diffusionless, lattice distortive, shear dominant transformation by nucleation and growth . In this work we present ab initio zero temperature calculations for two model systems, FeaNi and CuZn close in concentration to the martensitic region. Iron-nickel is a typical representative of the ferrous alloys with fee bet transition whereas the copper-zink alloy undergoes a transformation from the open to close packed structure. ... 

Copper-base alloys will corrode in aerated conditions. It is, therefore, sometimes appropriate to consider cathodic protection. It becomes particularly relevant when the flow rates are high or when the design of an item causes the copper to be an anode in a galvanic cell (e.g. a copper alloy tube plate in a titanium-tubed heat exchanger). Corrosion can be controlled by polarisation to approximately — 0-6V (vs. CU/CUSO4) and may be achieved using soft iron sacrificial anodes. 

Both iron- and copper-based alloys are corroded more easily on either side of the neutral pH band. In low pH conditions e.g. due to carbon dioxide, the acidic environments attack the alloys readily, causing damage both at the points of initial corrosion and perhaps, consequentially, further along the system, by screening the surface with corrosion products and permitting the development of differential aeration cells. 

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