Copper alloys are metal Alloy that have copper as their principal component. They have high resistance against corrosion. Of the large number of different types, the best known traditional types are bronze, where tin is a significant addition, and brass, using zinc instead. Both of these are imprecise terms. Latten is a further term, mostly used for coins with a very high copper content. Today the term "copper alloy" tends to be substituted for all of these, especially by museums. British Museum, "Scope Note" for "copper alloy"
Copper deposits are abundant in most parts of the world (globally 70 parts per million), and it has therefore always been a relatively cheap metal. By contrast, tin is relatively rare (2 parts per million), and in Europe and the Mediterranean region, even in prehistoric times, it had to be traded considerable distances and was expensive, sometimes virtually unobtainable. Zinc is even more common at 75 parts per million but is harder to extract from its ores. Bronze with the ideal percentage of tin was therefore expensive, and the proportion of tin was often reduced to save cost. The discovery and exploitation of the Bolivian tin belt in the 19th century made tin far cheaper, although forecasts for future supplies are less positive.
There are as many as 400 different copper and copper alloy compositions loosely grouped into the categories: copper, high copper alloy, brasses, bronzes, cupronickel, copper–nickel–zinc (nickel silver), leaded copper, and special alloys.
+Classification of copper and its alloys |
C1xxxx–C4xxxx,C66400–C69800 |
C5xxxx |
C60600–C64200 |
C64700–C66100 |
C7xxxx |
+Mechanical properties of common copper alloysLyons, William C. and Plisga, Gary J. (eds.) Standard Handbook of Petroleum & Natural Gas Engineering, Elsevier, 2006 | |||||||
Copper (ASTM B1, B2, B3, B152, B124, R133) | Cu 99.9 | Annealed | 10 | 32 | 45 | 42 | Electrical equipment, roofing, screens |
Cold-drawn | 40 | 45 | 15 | 90 | |||
Cold-rolled | 40 | 46 | 5 | 100 | |||
Gilding metal (ASTM B36) | Cu 95.0, Zn 5.0 | Cold-rolled | 50 | 56 | 5 | 114 | Coins, bullet jackets |
Cartridge brass (ASTM B14, B19, B36, B134, B135) | Cu 70.0, Zn 30.0 | Cold-rolled | 63 | 76 | 8 | 155 | Good for cold-working; , hardware, electrical, drawn cartridge cases. |
Phosphor bronze (ASTM B103, B139, B159) | Cu 89.75, Sn 10.0, P 0.25 | Spring temper | — | 122 | 4 | 241 | High fatigue-strength and spring qualities |
Yellow or High brass (ASTM B36, B134, B135) | Cu 65.0, Zn 35.0 | Annealed | 18 | 48 | 60 | 55 | Good corrosion resistance |
Cold-drawn | 55 | 70 | 15 | 115 | |||
Cold-rolled (HT) | 60 | 74 | 10 | 180 | |||
Manganese bronze (ASTM 138) | Cu 58.5, Zn 39.2, Fe 1.0, Sn 1.0, Mn 0.3 | Annealed | 30 | 60 | 30 | 95 | |
Cold-drawn | 50 | 80 | 20 | 180 | |||
Naval brass (ASTM B21) | Cu 60.0, Zn 39.25, Sn 0.75 | Annealed | 22 | 56 | 40 | 90 | Resistance to salt corrosion |
Cold-drawn | 40 | 65 | 35 | 150 | |||
Muntz metal (ASTM B111) | Cu 60.0, Zn 40.0 | Annealed | 20 | 54 | 45 | 80 | Condenser tubes |
Aluminium bronze (ASTM B169 alloy A, B124, B150) | Cu 92.0, Al 8.0 | Annealed | 25 | 70 | 60 | 80 | — |
Hard | 65 | 105 | 7 | 210 | |||
Beryllium copper (ASTM B194, B196, B197) | Cu 97.75, Be 2.0, Co or Ni 0.25 | Annealed, solution-treated | 32 | 70 | 45 | B60 (Rockwell scale) | National Bronze & Metals > Beryllium Copper |
Cold-rolled | 104 | 110 | 5 | B81 (Rockwell) | |||
Free-cutting brass | Cu 62.0, Zn 35.5, Pb 2.5 | Cold-drawn | 44 | 70 | 18 | B80 (Rockwell) | Screws, nuts, gears, keys |
Nickel silver (ASTM B122) | Cu 65.0, Zn 17.0, Ni 18.0 | Annealed | 25 | 58 | 40 | 70 | Hardware |
Cold-rolled | 70 | 85 | 4 | 170 | |||
Nickel silver (ASTM B149) | Cu 76.5, Ni 12.5, Pb 9.0, Sn 2.0 | Cast | 18 | 35 | 15 | 55 | Lewis Brass & Company > Copper Alloy Data |
Cupronickel (ASTM B111, B171) | Cu 88.35, Ni 10.0, Fe 1.25, Mn 0.4 | Annealed | 22 | 44 | 45 | – | Condenser, salt-water pipes |
Cold-drawn tube | 57 | 60 | 15 | – | |||
Cupronickel | Cu 70.0, Ni 30.0 | Wrought | – | – | – | – | Heat-exchange equipment, valves |
Ounce metal Cast copper alloy C83600 (Ounce Metal) substech.com Copper alloy C83600 (also known as "Red brass" or "composition metal") (ASTM B62) | Cu 85.0, Zn 5.0, Pb 5.0, Sn 5.0 | Cast | 17 | 37 | 25 | 60 | — |
Gunmetal (known as "red brass" in US) | Varies Cu 80-90%, Zn <5%, Sn ~10%, +other elements@ <1% |
+ Mechanical properties of Copper Development Association (CDA) copper alloys | ||||||||||
35 | ||||||||||
84 | ||||||||||
90 | ||||||||||
90 | ||||||||||
90 | ||||||||||
30 | ||||||||||
8 | ||||||||||
26 | ||||||||||
30 | ||||||||||
30 | ||||||||||
20 | ||||||||||
42 | ||||||||||
42 | ||||||||||
40 | ||||||||||
45 | ||||||||||
70 | ||||||||||
70 | ||||||||||
70 | ||||||||||
80 | ||||||||||
80 | ||||||||||
80 | ||||||||||
80 | ||||||||||
50 | ||||||||||
55 | ||||||||||
60 | ||||||||||
50 | ||||||||||
50 | ||||||||||
40 | ||||||||||
† Brinell scale with 3000 kg load |
+ Comparison of copper alloy standards. |
C-2229 Gr2 |
C-2229 Gr9 |
C-2229 Gr8 |
C-2229 Gr7 |
C-2229 Gr1 |
B-16541 |
C-15345 Gr10 |
C-15345 Gr12 |
C-22229 Gr3 |
C-22229 Gr5 |
C-15345 Gr13 |
C-22229 Gr8 |
The following table outlines the chemical composition of various grades of copper alloys.
+ Chemical composition of copper alloys. | |||||||||||
Mn 4 | |||||||||||
Mn 3 | |||||||||||
Mn 3 | |||||||||||
Mn 0.25 | |||||||||||
Ni 2 | |||||||||||
Si 2 | |||||||||||
Mn 12 | |||||||||||
Mn 1 | |||||||||||
Si 4 | |||||||||||
Si 3 | |||||||||||
Si 4 | |||||||||||
Si 4.5 | |||||||||||
Si 4 | |||||||||||
Si 1 | |||||||||||
† Chemical composition may vary to yield mechanical properties |
Brasses can be sensitive to selective leaching corrosion under certain conditions, when zinc is leached from the alloy ( dezincification), leaving behind a spongy copper structure.
Fe†, Hg†, Sn†, Zn† |
Hg† |
17.5 Zn, 11.5 Ni, |
C (type I diamond) |
0-4 Cd |
Mn† |
Pb sulfides† |
Fe†, Sn†, Pb†, Zn†, |
5-6 Al |
Ni†, Sn† |
Ni†, Zn† |
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