List of copper alloys

Example of a copper alloy object: a Neo-Sumerian "Foundation Nail" of Gudea, circa 2100 BC, made in the lost-wax cast method, overall: 17.5 x 4.5 x 7.3 cm, probably from modern-day Iraq, now in the Cleveland Museum of Art (Cleveland, Ohio, USA)

Copper alloys are metal alloys 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.[1]

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, and even in prehistoric times 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.

Composition

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The similarity in external appearance of the various alloys, along with the different combinations of elements used when making each alloy, can lead to confusion when categorizing the different compositions. The following table lists the principal alloying element for four of the more common types used in modern industry, along with the name for each type. Historical types, such as those that characterize the Bronze Age, are vaguer as the mixtures were generally variable.

Classification of copper and its alloys
Family Principal alloying element UNS numbers
Copper alloys, brass Zinc (Zn) C1xxxx–C4xxxx,C66400–C69800
Phosphor bronze Tin (Sn) C5xxxx
Aluminium bronzes Aluminium (Al) C60600–C64200
Silicon bronzes Silicon (Si) C64700–C66100
Cupronickel, nickel silvers Nickel (Ni) C7xxxx
Mechanical properties of common copper alloys[2]
Name Nominal composition (percentages) Form and condition Yield strength (0.2% offset, ksi) Tensile strength (ksi) Elongation in 2 inches (percent) Hardness (Brinell scale) Comments
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; radiators, 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 Forgings
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 Condensor 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) Electrical, valves, pumps, oilfield tools, aerospace landing gears, robotic welding, mold making [3]
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 Easy to machine; ornaments, plumbing [4]
Cupronickel (ASTM B111, B171) Cu 88.35, Ni 10.0, Fe 1.25, Mn 0.4 Annealed 22 44 45 Condensor, salt-water pipes
Cold-drawn tube 57 60 15
Cupronickel Cu 70.0, Ni 30.0 Wrought Heat-exchange equipment, valves
Ounce metal[5] 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[6]
Family CDA Tensile strength [ksi] Yield strength [ksi] Elongation (typ.) [%] Hardness
[Brinell 10 mm-500 kg]
Machinability [YB = 100]
Min. Typ. Min. Typ.
Red brass 833 32 10 35 35 35
836 30 37 14 17 30 50–65 84
838 29 35 12 16 25 50–60 90
Semi-red brass 844 29 34 13 15 26 50–60 90
848 25 36 12 14 30 50–60 90
Manganese bronze 862 90 95 45 48 20 170–195 30
863 110 119 60 83 18 225 8
865 65 71 25 28 30 130 26
Tin bronze 903 40 45 18 21 30 60–75 30
905 40 45 18 22 25 75 30
907 35 44 18 22 20 80 20
Leaded tin bronze 922 34 40 16 20 30 60–72 42
923 36 40 16 20 25 60–75 42
926 40 44 18 20 30 65–80 40
927 35 42 21 20 77 45
High-leaded tin bronze 932 30 35 14 18 20 60–70 70
934 25 32 16 20 55–65 70
935 25 32 12 16 30 55–65 70
936 33 30 16 21 15 79-83 80
937 25 35 12 18 20 55–70 80
938 25 30 14 16 18 50–60 80
943 21 27 13 10 42–55 80
Aluminium bronze 952 65 80 25 27 35 110–140 50
953 65 75 25 27 25 140 55
954 75 85 30 35 18 140–170 60
955 90 100 40 44 12 180–200 50
958 85 95 35 38 25 150-170 50
Silicon bronze 878 80 83 30 37 29 115 40
Brinell scale with 3000 kg load
Comparison of copper alloy standards[6]
Family CDA ASTM SAE SAE superseded Federal Military
Red brass 833
836 B145-836 836 40 QQ-C-390 (B5) C-2229 Gr2
838 B145-838 838 QQ-C-390 (B4)
Semi-red brass 844 B145-844 QQ-C-390 (B2)
848 B145-848 QQ-C-390 (B1)
Manganese bronze 862 B147-862 862 430A QQ-C-390 (C4) C-2229 Gr9
863 B147-863 863 430B QQ-C-390 (C7) C-2229 Gr8
865 B147-865 865 43 QQ-C-390 (C3) C-2229 Gr7
Tin bronze 903 B143-903 903 620 QQ-C-390 (D5) C-2229 Gr1
905 B143-905 905 62 QQ-C-390 (D6)
907 907 65
Leaded tin bronze 922 B143-922 922 622 QQ-C-390 (D4) B-16541
923 B143-923 923 621 QQ-C-390 (D3) C-15345 Gr10
926 926
927 927 63
High-leaded tin bronze 932 B144-932 932 660 QQ-C-390 (E7) C-15345 Gr12
934 QQ-C-390 (E8) C-22229 Gr3
935 B144-935 935 66 QQ-C-390 (E9)
937 B144-937 937 64 QQ-C-390 (E10)
938 B144-938 938 67 QQ-C-390 (E6)
943 B144-943 943 QQ-C-390 (E1)
Aluminium bronze 952 B148-952 952 68A QQ-C-390 (G6) C-22229 Gr5
953 B148-953 953 68B QQ-C-390 (G7)
954 B148-954 954 QQ-C-390 (G5) C-15345 Gr13
955 B148-955 955 QQ-C-390 (G3) C-22229 Gr8
958 QQ-C-390 (G8)
Silicon bronze 878 B30 878

The following table outlines the chemical composition of various grades of copper alloys.

Chemical composition of copper alloys[6][7]
Family CDA AMS UNS Cu [%] Sn [%] Pb [%] Zn [%] Ni [%] Fe [%] Al [%] Other [%]
Red brass 833 C83300 93 1.5 1.5 4
C83400[8] 90 10
836 4855B C83600 85 5 5 5
838 C83800 83 4 6 7
Semi-red brass 844 C84400 81 3 7 9
845 C84500 78 3 7 12
848 C84800 76 3 6 15
Manganese bronze C86100[9] 67 0.5 21 3 5 Mn 4
862 C86200 64 26 3 4 Mn 3
863 4862B C86300 63 25 3 6 Mn 3
865 4860A C86500 58 0.5 39.5 1 1 Mn 0.25
Tin bronze 903 C90300 88 8 4
905 4845D C90500 88 10 0.3 max 2
907 C90700 89 11 0.5 max 0.5 max
Leaded tin bronze 922 C92200 88 6 1.5 4.5
923 C92300 87 8 1 max 4
926 4846A C92600 87 10 1 2
927 C92700 88 10 2 0.7 max
High-leaded tin bronze 932 C93200 83 7 7 3
934 C93400 84 8 8 0.7 max
935 C93500 85 5 9 1 0.5 max
937 4842A C93700 80 10 10 0.7 max
938 C93800 78 7 15 0.75 max
943 4840A C94300 70 5 25 0.7 max
Aluminium bronze 952 C95200 88 3 9
953 C95200 89 1 10
954 4870B
4872B
C95400 85 4 11
C95410[10] 85 4 11 Ni 2
955 C95500 81 4 4 11
C95600[11] 91 7 Si 2
C95700[12] 75 2 3 8 Mn 12
958 C95800 81 5 4 9 Mn 1
Silicon bronze C87200[13] 89 Si 4
C87400[14] 83 14 Si 3
C87500[15] 82 14 Si 4
C87600[16] 90 5.5 Si 4.5
878 C87800[17] 80 14 Si 4
C87900[18] 65 34 Si 1
Chemical composition may vary to yield mechanical properties

Brasses

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Binary Cu Si phase diagram, the base phase diagram for silicon bronzes generated using NIMS Open databases https://cpddb.nims.go.jp/cpddb/cu-ehttps://cpddb.nims.go.jp/cpddb/cu-elem/cusi/cusi.htm - DOI https://doi.org/10.48505/nims.3060 and Computherm Pandat https://computherm.com/
Binary Cu Si phase diagram, the base phase diagram for silicon bronzes
Binary Cu Al phase diagram, the base phase diagram for aluminium bronzes
Binary Cu Al phase diagram, the base phase diagram for aluminium bronzes, generated using NIMS Open databases https://cpddb.nims.go.jp/cpddb/al-elem/alcu/alcu.htm - DOI https://doi.org/10.48505/nims.3060 and Computherm Pandat https://computherm.com/
Binary Cu Sn phase diagram
Binary Cu Sn phase diagram, the base phase diagram for bronzes, generated using NIMS Open databases https://cpddb.nims.go.jp/cpddb/cu-elem/cusn/cusn.htm - DOI https://doi.org/10.48505/nims.3060 and Computherm Pandat https://computherm.com/
Cu Zn binary phase diagram. Base phase diagram for brasses
Binary Cu Zn phase diagram, the base phase diagram for brasses, generated using NIMS Open database https://cpddb.nims.go.jp/cpddb/cu-elem/cu_index.htm  Cu-Zn - DOI https://doi.org/10.48505/nims.3060 and Computherm Pandat https://computherm.com/

A brass is an alloy of copper with zinc. Brasses are usually yellow in colour. The zinc content can vary between few % to about 40%; as long as it is kept under 15%, it does not markedly decrease corrosion resistance of copper.

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.

Bronzes

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A bronze is an alloy of copper and other metals, most often tin, but also aluminium and silicon.

Precious metal alloys

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Copper is often alloyed with precious metals like gold (Au) and silver (Ag).

Name Cu [%] Au [%] Ag [%] Other [%]
Auricupride
Ashtadhatu Fe†, Hg†, Sn†, Zn†
Billon Hg†
Chinese silver 58 2 17.5 Zn, 11.5 Ni,
Corinthian bronze
CuSil 28 72
Dymalloy 20 80 C (type I diamond)
Electrum, Green gold 6-23 75-80 0-15 0-4 Cd
Grey gold Mn†
Guanín 25 56 18
Hepatizon trace trace
Niello Pb sulfides†
Panchaloha Fe†, Sn†, Pb†, Zn†,
Rose, red, and pink gold 20-50 50-75 0-5
Spangold 18-19 76 5-6 Al
Shakudō 90-96 4-10
Shibuichi 40-77 0-1 23-60
Tibetan silver Ni†, Sn†
Tumbaga 3-97 3-97
White gold Ni†, Zn†

† amount unspecified

See also

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References

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  1. ^ British Museum, "Scope Note" for "copper alloy"
  2. ^ Lyons, William C. and Plisga, Gary J. (eds.) Standard Handbook of Petroleum & Natural Gas Engineering, Elsevier, 2006
  3. ^ National Bronze & Metals | Beryllium Copper
  4. ^ Lewis Brass & Company | Copper Alloy Data Archived 2021-05-12 at the Wayback Machine
  5. ^ Cast copper alloy C83600 (Ounce Metal) substech.com
  6. ^ a b c Industrial Investment Castings - Franklin Bronze, retrieved 2009-09-07.
  7. ^ Brass and Bronze Alloys, archived from the original on 2009-08-25, retrieved 2009-09-08.
  8. ^ UNS C83400, retrieved 2009-09-08.
  9. ^ UNS C86100, retrieved 2009-09-08.
  10. ^ UNS C95410, retrieved 2009-09-08.
  11. ^ UNS C95600, retrieved 2009-09-08.
  12. ^ UNS C95700, retrieved 2009-09-08.
  13. ^ UNS C87200, retrieved 2009-09-08.
  14. ^ UNS C87400, retrieved 2009-09-08.
  15. ^ UNS C87500, retrieved 2009-09-08.
  16. ^ UNS C87600, retrieved 2009-09-08.
  17. ^ UNS C87800, retrieved 2009-09-08.
  18. ^ UNS C87900, retrieved 2009-09-08.
  19. ^ "Doehler-Jarvis Company Collection, MSS-202".
  20. ^ Woldman’s Engineering Alloys, 9th Edition 1936, American Society for Metals, ISBN 978-0-87170-691-1

Bibliography

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  • Oberg, Erik; Jones, Franklin D.; Horton, Holbrook L. (1992). Machinery's Handbook (24 ed.). New York: Industrial Press Inc. p. 501. ISBN 0-8311-2492-X.
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