Copper alloys composition

Aluminum drillpipe is generally made of 2014 type aluminum-copper alloy. Composition of this alloy is 0.50 to 1.20% silicon, 1.00% iron maximum, 3.90 to 5.0% copper, 0.40 to 1.20% manganese, 0.25% zinc maximum and 0.05% titanium. The alloy is heat treated to T6 conditions that represent 64 ksi tensile strength, 58 Ksi yield strength, 7% elongation and a Hbn of 135- Aluminum drillpipe generally comes with steel tool joints that are threaded on to ensure maximum strength that cannot be attained with aluminum joints. 

The main goal of this study was to identify different copper alloy compositions and relate them to different foundries or casting techniques. When considering the tin and the zinc contents in the sculptures, three different groups... 

A1 substituted in one-third of top-layer Cu sites, second layer pure Cu, no buckling in top layer, layer spacing is 2.05 0.05 A, the same as bulk copper. Alloy composition 16% A1 atoms in Cu. 

Way JD. Palladium/Copper alloy composite membrtines for high temperature hydrogen separation from coal-derived gas streams. Annutil Progress Report, DE-FG26-99FT40585, 2004. 

Only lead alloys containing copper below 0.08% have practical appHcations. Lead sheet, pipe, cable sheathing, wine, and fabricated products are produced from lead—copper alloys having copper contents near the eutectic composition. Lead—copper alloys in the range 0.03—0.08 wt % copper are covered by many specifications ASTM B29-92 (7), QQL 171 (United States), BS 334, HP2 Type 11 (Canada), DIN 1719 (Germany), and AS 1812 (Austraha). 

A third group includes silver—nickel, silver—cadmium oxide, and silver—graphite combinations. These materials are characterized by low contact resistance, some resistance to arc erosion, and excellent non sticking characteristics. They can be considered intermediate in overall properties between silver alloys and silver or copper—refractory compositions. Silver—cadmium oxide compositions, the most popular of this class, have wide appHcation in aircraft relays, motor controllers, and line starters and controls. 

Phosphorized deoxidized arsenical copper (alloy 142 (23)) is used for heat exchangers and condenser tubes. Copper-arsenical leaded Muntz metal (alloy 366), Admiralty brass (alloy 443), naval brass (alloy 465), and aluminum brass (alloy 687), all find use in condensers, evaporators, ferrules, and heat exchanger and distillation tubes. The composition of these alloys is Hsted in Table 5. 

Greater amounts of copper increase the proportion of needles or stars of Cu Sn in the microstmcture. Increase in antimony above 7.5% results in antimony—tin cubes. Hardness and tensile strength increase with copper and antimony content ductiUty decreases. Low percentages of antimony (3—7%) and copper (2—4%) provide maximum resistance to fatigue cracking in service. Since these low alloy compositions are relatively soft and weak, compromise between fatigue resistance and compressive strength is often necessary. 

The oxidation of nickel-copper alloys provides an example of die dependence of the composition of the oxide layer on the composition of the alloy. Nickel-copper alloys depart from Raoult s law, but as a first approximation can be taken as ideal. The Gibbs energy change for the reaction... 

Typical marine propellers are fixed pitch and small in diameter with veiy thin, but broad, blade sections. They are made from either cast metal, corrosion-resistant metal alloys such as copper, or composite materials. Marine propellers normally operate at 60 percent efficiency due to the proximity of the ship s hull, which limits the overall diameter of the propeller and disturbs the efficient flow of water through the blades. As a result, the blades have to be veiy wide to produce adequate thrust. Marine propeller designers use innovations such as overlapping blades and wheel vanes to offset those problems and improve efficiency. 

It can be seen from Table 1.16 that differences in composition (nature or concentration) of the environment can lead to localised attack, and in Section 1.4 it was shown how differences in the activity of silver ions can give rise to a reversible concentration cell in which the silver electrodes in contact with the solution containing the lower and higher concentration of Ag ions are the anode and cathode, respectively. Concentration cells of this type are rare in practice, but can occur during the corrosion of copper and copper alloys. 

The mechanical properties of wrought alloys depend on composition and metallurgical condition. At the extremes, annealed pure copper has a tensile strength of 180MN m and a hardness of 40 Hy, and heat-treated beryllium copper can have a tensile strength of 1 300 MN m and a hardness of 390 Hy. Summaries of typical properties of some of the more important wrought and cast copper alloys are given in Tables 4.9 and 4.10. 

Typical alloy compositions are reported by Hochmann etal. (Table 8.2) . Molybdenum or copper is added to some of the alloys. 

Copper alloys are particularly prone to attack by long-chain fatty acids which are often present in sealing compositions, temporary protectives and as trace additives in many plastics under acid conditions ester plasticisers may saponify in the presence of copper giving rapid corrosion of the copper and accelerating degradation of the polymer. 

Small variations in solution composition may also affect the value of any critical velocity. In laboratory tests using recirculating artificial sea-water the presence of dissolved copper from copper alloy test-pieces has been shown to affect the value of the critical velocity for such materials . 

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