Composition · copper alloys
What is bronze made of? Tin, aluminium, silicon and beryllium bronzes
Bronze is copper alloyed with a second main ingredient: tin and phosphorus in Phosphor bronze UNS C51000 (CuSn5P) and Phosphor bronze UNS C52100 (CuSn8), aluminium and iron in Aluminium bronze UNS C63000 (wrought, CuAl10Ni5Fe4) and Aluminium bronze UNS C95400, and silicon and manganese in Silicon bronze UNS C65500 (CuSi3Mn1). Only 2 of these 5 bronze profiles in the Space Mushroom database print tin as an ingredient; the limits are wt % as printed by suppliers such as Concast, National Bronze and Austral Wright.
Words used on this page
- wt %
- Percent by weight of the alloy. A limit printed as "max" is a cap on an impurity or a minor addition, not a main ingredient.
- UNS
- Unified Numbering System, the C-number that names a copper alloy, for example UNS C52100.
- Balance
- The share of the alloy left after every other ingredient, usually copper.
- Temper
- The strength state of a metal after cold working or heat treatment, such as H04 hard or annealed.
1
Which metals is bronze made of?
Bronze is copper alloyed with a second main ingredient: tin and phosphorus in phosphor bronze UNS C51000 and UNS C52100, aluminium and iron in aluminium bronze UNS C63000 and UNS C95400, or silicon and manganese in silicon bronze UNS C65500. Only 2 of the 5 bronze profiles in the Space Mushroom database print tin as an ingredient. Copper is the base of every one.
Each card is one alloy, drawn as a copper-balance bar: every ingredient runs from its lower printed limit (solid) to its upper limit (hatched), and copper, or zinc in brass, fills the rest. With scripts on, tap ingredients to keep only the alloys that contain all of them. The bar is an aid; the numbers are in the text on every card and in the table in section 2.
The shelf: 12 copper alloys, each with its printed limits in wt %
-
Phosphor bronze UNS C51000 (CuSn5P)
phosphor bronzenamed a bronze in its profile
- Sn 4.20 to 5.80
- P 0.03 to 0.35
- Pb 0.05 max
- Zn 0.30 max
- Fe 0.10 max
- Cu balance (93.6 to 95.6)
Phosphor bronze UNS C51000 (CuSn5P) is copper with 4.20 to 5.80 wt% tin and 0.03 to 0.35 wt% phosphorus, and at most 0.05 wt% lead, 0.30 wt% zinc and 0.10 wt% iron (per Concast).
485 MPa minimum tensile strength in H04 hard, 1/4 to 1/2 inch round and hexagonal (per Concast); 15 %IACS electrical conductivity (68 °F (20 °C), per Concast).
-
Phosphor bronze UNS C52100 (CuSn8)
phosphor bronzenamed a bronze in its profile
- Sn 7.00 to 9.00
- P 0.03 to 0.35
- Pb 0.05 max
- Zn 0.20 max
- Fe 0.10 max
- Cu balance
Phosphor bronze UNS C52100 (CuSn8) is copper with 7.00 to 9.00 wt% tin and 0.03 to 0.35 wt% phosphorus, and at most 0.05 wt% lead, 0.20 wt% zinc and 0.10 wt% iron (per Concast).
585 MPa minimum tensile strength in H04 hard, 1/4 to 1/2 inch round and hexagonal (per Concast); 13 %IACS electrical conductivity (68 °F (20 °C), per Concast).
-
Aluminium bronze UNS C63000 (wrought, CuAl10Ni5Fe4)
aluminium bronzenamed a bronze in its profile
- Al 9.0 to 11.0
- Ni 4.0 to 5.5
- Fe 2.0 to 4.0
- Mn 1.5 max
- Pb 0.05 max
- Cu balance
Aluminium bronze UNS C63000 (wrought, CuAl10Ni5Fe4) is copper with 9.0 to 11.0 wt% aluminium, 4.0 to 5.5 wt% nickel and 2.0 to 4.0 wt% iron, and at most 1.5 wt% manganese and 0.05 wt% lead (per National Bronze).
760 MPa tensile strength in round bar, 25 mm and under (per Smith Metal); 7 %IACS electrical conductivity (68 °F (20 °C), per National Bronze).
-
Aluminium bronze UNS C95400
aluminium bronzenamed a bronze in its profile
- Al 10.00 to 11.50
- Fe 3.00 to 5.00
- Ni 1.50 max
- Mn 0.50 max
- Cu balance (83.00 min)
Aluminium bronze UNS C95400 is copper with 10.00 to 11.50 wt% aluminium and 3.00 to 5.00 wt% iron, and at most 1.50 wt% nickel and 0.50 wt% manganese (per Concast).
586 MPa minimum tensile strength in continuous cast, standard sheet, as cast (per Concast); 13 %IACS electrical conductivity (68 °F (20 °C), per Concast).
-
Silicon bronze UNS C65500 (CuSi3Mn1)
silicon bronzenamed a bronze in its profile
- Si 2.8 to 3.8
- Mn 0.50 to 1.3
- Fe 0.8 max
- Zn 1.5 max
- Ni 0.6 max
- Pb 0.05 max
- Cu balance
Silicon bronze UNS C65500 (CuSi3Mn1) is copper with 2.8 to 3.8 wt% silicon and 0.50 to 1.3 wt% manganese, and at most 0.8 wt% iron, 1.5 wt% zinc, 0.6 wt% nickel and 0.05 wt% lead (per Austral Wright).
538 MPa tensile strength in H02, flat product (per Austral Wright); 7 %IACS electrical conductivity (68 degF (20 degC), per Austral Wright).
-
Beryllium copper (UNS C17200)
beryllium copper
- Be 1.80 to 2.00
- Ni+Co 0.20 min
- Ni+Co+Fe 0.6 max
- Cu balance
Beryllium copper (UNS C17200) is copper with 1.80 to 2.00 wt% beryllium and at least 0.20 wt% nickel plus cobalt, and at most 0.6 wt% nickel plus cobalt plus iron together (per Materion).
1140 to 1380 MPa tensile strength in AT (TF00), precipitation age-hardened, 0.030 to 3 in (0.76 to 76 mm) diameter or thickness, 600 to 675 °F (315 to 357 °C), after 3 hours (per Materion); 25 to 30 %IACS electrical conductivity (precipitation age-hardened (heat treated), per Materion).
-
Cupronickel 70/30 (UNS C71500)
cupronickel
- Ni 29.0 to 33.0
- Fe 0.4 to 1.0
- Mn 1.0 max
- Cu balance
Cupronickel 70/30 (UNS C71500) is copper with 29.0 to 33.0 wt% nickel and 0.4 to 1.0 wt% iron, and at most 1.0 wt% manganese (per JTCopper).
358 to 414 MPa tensile strength in 060 soft anneal (ASTM B 151), rod and bar, diameter up to 12 mm (per Wieland); 5 %IACS electrical conductivity (68 ºF as printed (about 20 °C), per Wieland).
- The JTCopper table prints a copper row of 65.0 to 70.0, which does not fit its other rows, so copper is shown as the balance.
-
Nickel silver UNS C75200
nickel silver
- Cu 63.0 to 66.5
- Ni 16.5 to 19.5
- Pb 0.05 max
- Fe 0.25 max
- Mn 0.50 max
- Zn balance
Nickel silver UNS C75200 is an alloy of copper 63.0 to 66.5 wt% with 16.5 to 19.5 wt% nickel and zinc as the balance, and at most 0.05 wt% lead, 0.25 wt% iron and 0.50 wt% manganese (per Fisk).
370 to 430 MPa tensile strength in H90, soft annealed (R370), strip (per Matthey); 6 %IACS electrical conductivity (annealed, per Fisk).
A second source prints different limits
Matthey CuNi18Zn20 (EN CW409J) limits (Matthey)
- Cu 60.0 to 63.0
- Ni 17.0 to 19.0
- Fe 0.30 max
- Mn 0.50 max
- Pb 0.03 max
- Sn 0.03 max
- Zn balance
- ASTM B122 prints the nominal composition of UNS C75200 as copper 65, nickel 18, zinc 17 (wt %), with no limits.
-
- Cu 60.0 to 63.0
- Pb 2.5 to 3.0
- Fe 0.35 max
- Zn balance
Free-cutting brass UNS C36000 is an alloy of copper 60.0 to 63.0 wt% with 2.5 to 3.0 wt% lead and zinc as the balance, and at most 0.35 wt% iron (per Aviva).
390 MPa minimum tensile strength in H02, half hard (1/2 hard), round rod, mill limits 1.59 to 6.35 mm (per Fisk); 26 %IACS electrical conductivity (H02, 1/2 hard, per Aviva).
- Wikipedia prints lead 2.5 to 3.7 wt% for C360, a wider range than the Aviva and Fisk limits.
-
- Cu 68.5 to 71.5
- Pb 0.07 max
- Fe 0.05 max
- Zn balance
Cartridge brass 70/30 (UNS C26000) is an alloy of copper 68.5 to 71.5 wt% with zinc as the balance, and at most 0.07 wt% lead and 0.05 wt% iron (per Aviva).
427 MPa tensile strength in H02, half hard, flat product (sheet, strip and plate), 1 in rows (per Aviva); 28 %IACS electrical conductivity (68 °F (20 °C), per Aviva).
-
- Cu 57.0 to 59.0
- Pb 2.5 to 3.5
- Fe 0.30 max
- Ni 0.30 max
- Zn balance
Leaded free-machining brass CW614N (CuZn39Pb3, UNS C38500) is an alloy of copper 57.0 to 59.0 wt% with 2.5 to 3.5 wt% lead and zinc as the balance, and at most 0.30 wt% iron and 0.30 wt% nickel (per HME).
430 MPa minimum tensile strength in R430, rod, diameter 2 to 40 mm (per Brassland); 25 %IACS electrical conductivity (per HME).
-
- O 10 ppm max
- Cu balance (99.95 min)
Copper (oxygen-free grade C10200) is at least 99.95 wt% copper with at most 10 ppm oxygen (per Aurubis).
179 to 262 MPa tensile strength in soft, strip, rolled product (Aurubis) (per Aurubis); 58 MS/m, printed as equal to 100 %IACS electrical conductivity (soft, per Aurubis).
2
What is in phosphor bronze, aluminium bronze, silicon bronze and beryllium copper?
Phosphor bronze UNS C52100 holds 7.00 to 9.00 wt% tin and 0.03 to 0.35 wt% phosphorus (per Concast). Aluminium bronze UNS C63000 holds 9.0 to 11.0 wt% aluminium, 4.0 to 5.5 wt% nickel and 2.0 to 4.0 wt% iron (per National Bronze). Silicon bronze UNS C65500 holds 2.8 to 3.8 wt% silicon (per Austral Wright). Beryllium copper UNS C17200 holds 1.80 to 2.00 wt% beryllium (per Materion). Copper is the balance in each.
The table gives every ingredient column for all 12 profiles. A dash means the source prints no limit for that element. Where two sources print different limits for the same grade, both rows are shown. The Smith Metal page, quoted in the Aluminium bronze UNS C63000 (wrought, CuAl10Ni5Fe4) profile, calls that grade the most commonly used nickel aluminium bronze in America; its nickel limit is 4.0 to 5.5 wt%.
| Alloy and source | Copper, wt % | Tin, wt % | Aluminium, wt % | Silicon, wt % | Beryllium, wt % | Nickel, wt % | Phosphorus, wt % | Zinc, wt % | Lead, wt % | Iron, wt % | Manganese, wt % | Other |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Phosphor bronze UNS C51000 (CuSn5P)Concast composition table | balance (93.6 to 95.6) | 4.20 to 5.80 | – | – | – | – | 0.03 to 0.35 | 0.30 max | 0.05 max | 0.10 max | – | – |
| Phosphor bronze UNS C52100 (CuSn8)Concast composition table (ASTM B139) | balance | 7.00 to 9.00 | – | – | – | – | 0.03 to 0.35 | 0.20 max | 0.05 max | 0.10 max | – | – |
| Aluminium bronze UNS C63000 (wrought, CuAl10Ni5Fe4)National Bronze min/max table | balance | – | 9.0 to 11.0 | – | – | 4.0 to 5.5 | – | – | 0.05 max | 2.0 to 4.0 | 1.5 max | – |
| Aluminium bronze UNS C95400ASTM B505 limits as printed (Concast) | balance (83.00 min) | – | 10.00 to 11.50 | – | – | 1.50 max | – | – | – | 3.00 to 5.00 | 0.50 max | – |
| Silicon bronze UNS C65500 (CuSi3Mn1)Austral Wright composition table | balance | – | – | 2.8 to 3.8 | – | 0.6 max | – | 1.5 max | 0.05 max | 0.8 max | 0.50 to 1.3 | – |
| Beryllium copper (UNS C17200)Materion composition table | balance | – | – | – | 1.80 to 2.00 | 0.20 min (Ni+Co) | – | – | – | – | – | Ni+Co+Fe 0.6 max |
| Cupronickel 70/30 (UNS C71500)JTCopper composition table | balance | – | – | – | – | 29.0 to 33.0 | – | – | – | 0.4 to 1.0 | 1.0 max | – |
| Nickel silver UNS C75200Fisk C752 limits (UNS C75200 family) | 63.0 to 66.5 | – | – | – | – | 16.5 to 19.5 | – | balance | 0.05 max | 0.25 max | 0.50 max | – |
| Same grade, second sourceMatthey CuNi18Zn20 (EN CW409J) limits | 60.0 to 63.0 | 0.03 max | – | – | – | 17.0 to 19.0 | – | balance | 0.03 max | 0.30 max | 0.50 max | – |
| Free-cutting brass UNS C36000Aviva composition limits (Fisk prints the same) | 60.0 to 63.0 | – | – | – | – | – | – | balance | 2.5 to 3.0 | 0.35 max | – | – |
| Cartridge brass 70/30 (UNS C26000)Aviva composition table | 68.5 to 71.5 | – | – | – | – | – | – | balance | 0.07 max | 0.05 max | – | – |
| Leaded free-machining brass CW614N (CuZn39Pb3, UNS C38500)HME composition table (iron and nickel limits from Brassland) | 57.0 to 59.0 | – | – | – | – | 0.30 max | – | balance | 2.5 to 3.5 | 0.30 max | – | – |
| Copper (oxygen-free grade C10200)Aurubis C10200 datasheet | balance (99.95 min) | – | – | – | – | – | – | – | – | – | – | oxygen 10 ppm max |
- Cupronickel 70/30 (UNS C71500). The JTCopper table prints a copper row of 65.0 to 70.0, which does not fit its other rows, so copper is shown as the balance.
- Nickel silver UNS C75200. ASTM B122 prints the nominal composition of UNS C75200 as copper 65, nickel 18, zinc 17 (wt %), with no limits.
- Free-cutting brass UNS C36000. Wikipedia prints lead 2.5 to 3.7 wt% for C360, a wider range than the Aviva and Fisk limits.
3
What do tin, aluminium and the other ingredients do to strength and conductivity?
In the H04 hard temper (1/4 to 1/2 inch round and hexagonal) per Concast, phosphor bronze UNS C52100 with 7.00 to 9.00 wt% tin prints a minimum tensile strength of 585 MPa and phosphor bronze UNS C51000 with 4.20 to 5.80 wt% tin prints 485 MPa. Conductivity is 13 %IACS for the first and 15 %IACS for the second. In this pair, more tin goes with more strength and less conductivity.
Only two comparisons in our data hold the condition fixed. No profile isolates one ingredient, because the grades differ in several ingredients and in product form, so everything else below is a table of values with the condition printed beside each one, never averaged across tempers.
Tin, same temper and same data sheet
15 %IACS
13 %IACS
H04 hard, 1/4 to 1/2 inch round and hexagonal, per Concast. Elongation, minimum: 13 % against 12 %. Tensile strength is a minimum in both rows.
Beryllium copper, same alloy and same data sheet, two tempers
Beryllium copper (UNS C17200), per Materion. Tensile strength rises from 410 to 590 MPa in the first temper to 1140 to 1380 MPa in the second. Both rows are the same composition; only the temper differs, as the data sheet names them (solution annealed, then precipitation age-hardened).
| Alloy | Condition | Tensile strength, MPa | Yield strength, MPa | Elongation, % | Basis and caveat | Source |
|---|---|---|---|---|---|---|
| Phosphor bronze UNS C51000 (CuSn5P) | H04 hard, 1/4 to 1/2 inch round and hexagonal | 485 min | not printed | 13 min | – | Concast |
| Phosphor bronze UNS C51000 (CuSn5P), second condition | H02, wire, 2 mm diameter | 585 | 550 | 8 | 0.5 % extension under load | Sullins |
| Phosphor bronze UNS C52100 (CuSn8) | H04 hard, 1/4 to 1/2 inch round and hexagonal | 585 min | not printed | 12 min | – | Concast |
| Phosphor bronze UNS C52100 (CuSn8), second condition | H02 (1/2H) | 475 to 580 | 350 min | 25 min | – | Aurubis |
| Aluminium bronze UNS C63000 (wrought, CuAl10Ni5Fe4) | round bar, 25 mm and under | 760 | 470 | 10 | approximate testing, not a guarantee (supplier sheet) | Smith Metal |
| Aluminium bronze UNS C95400 | continuous cast, standard sheet, as cast | 586 min | 221 min | 12 min | minimum | Concast |
| Aluminium bronze UNS C95400, second condition | continuous cast, heat treated (C95400HT sheet) | 655 min | 310 min | 10 min | minimum | Concast |
| Silicon bronze UNS C65500 (CuSi3Mn1) | H02, flat product | 538 | 310 | 17 | 0.5 % extension under load | Austral Wright |
| Silicon bronze UNS C65500 (CuSi3Mn1), second condition | H04, flat product | 648 | 400 | not printed | 0.5 % extension under load | Austral Wright |
| Beryllium copper (UNS C17200) | AT (TF00), precipitation age-hardened, 0.030 to 3 in (0.76 to 76 mm) diameter or thickness, 600 to 675 °F (315 to 357 °C), after 3 hours | 1140 to 1380 | 1000 to 1210 | 4 to 10 | – | Materion |
| Beryllium copper (UNS C17200), second condition | A (TB00), solution annealed, 0.030 to 14 in (0.76 to 356 mm) diameter or thickness | 410 to 590 | 130 to 250 | 20 to 75 | – | Materion |
| Cupronickel 70/30 (UNS C71500) | 060 soft anneal (ASTM B 151), rod and bar, diameter up to 12 mm | 358 to 414 | 124 to 179 | 30 to 45 | – | Wieland |
| Nickel silver UNS C75200 | H90, soft annealed (R370), strip | 370 to 430 | not printed | 40 | – | Matthey |
| Nickel silver UNS C75200, second condition | H185, hard (R610), strip | 610 to 700 | not printed | 2 | – | Matthey |
| Free-cutting brass UNS C36000 | H02, half hard (1/2 hard), round rod, mill limits 1.59 to 6.35 mm | 390 min | 170 min | 7 min | minimum | Fisk |
| Free-cutting brass UNS C36000, second condition | O60, annealed (soft), round rod, mill limits 1.59 to 6.35 mm | 330 min | 130 min | 15 min | minimum | Fisk |
| Cartridge brass 70/30 (UNS C26000) | H02, half hard, flat product (sheet, strip and plate), 1 in rows | 427 | 359 | 25 | typical value, 20 °C | Aviva |
| Cartridge brass 70/30 (UNS C26000), second condition | OS050, annealed, flat product (sheet, strip and plate), 1 in rows | 324 | 103 | 62 | typical value, 20 °C | Aviva |
| Leaded free-machining brass CW614N (CuZn39Pb3, UNS C38500) | R430, rod, diameter 2 to 40 mm | 430 min | 220 min | 10 min | minimum | Brassland |
| Leaded free-machining brass CW614N (CuZn39Pb3, UNS C38500), second condition | R500, rod, diameter 2 to 14 mm | 500 min | 350 min | 5 min | minimum | Brassland |
| Copper (oxygen-free grade C10200) | soft, strip, rolled product (Aurubis) | 179 to 262 | 69 | 35 | Rp0.2 nominal | Aurubis |
| Alloy | Density, g/cm3 | Melting point, °C | Thermal conductivity, W/(m·K) | Thermal expansion, µm/(m·K) |
|---|---|---|---|---|
| Phosphor bronze UNS C51000 (CuSn5P) | 8.86Sullins; 20 °C | 954 to 1049Concast | 84Sullins; wire, 2 mm diameter, 20 °C | 17.8Sullins; 20 to 300 °C (68 to 570 °F) |
| Phosphor bronze UNS C52100 (CuSn8) | 8.79Aurubis; 20 °C | 882 to 1027Concast | 67Aurubis; 20 °C | 17.4Concast; 20 to 300 °C |
| Aluminium bronze UNS C63000 (wrought, CuAl10Ni5Fe4) | 7.58Aalco | 1060 to 1075Zollern 1035Aalco | 63Zollern; 20 °C 37.7Aalco | 15Zollern; 20 to 100 °C 17Zollern; 20 to 300 °C |
| Aluminium bronze UNS C95400 | 7.45Concast; 20 °C | 1027Concast 1038Concast | 58.7Aviva; 20 °C | 16.2Aviva; 20 to 300 °C 15.5Concast; 20 to 300 °C |
| Silicon bronze UNS C65500 (CuSi3Mn1) | 8.53Austral Wright; 20 degC | 971 to 1027Austral Wright | 36.3Austral Wright; 20 degC | 18Austral Wright; 20 to 300 degC |
| Beryllium copper (UNS C17200) | 8.36Materion; precipitation age-hardened (heat treated) | 870Materion; solidus | 105Materion; precipitation age-hardened (heat treated), 25 °C | 17.5Materion |
| Cupronickel 70/30 (UNS C71500) | 8.94Wieland | 1170 to 1240Wieland | 29Wieland; 20 °C 29 to 33JTCopper | 13.2 to 16.2JTCopper; 20 to 300 °C |
| Nickel silver UNS C75200 | 8.7Matthey 0.316 lb/in3Fisk | 1060 to 1110Matthey | 32Matthey; 20 °C | 17.7Matthey |
| Free-cutting brass UNS C36000 | 8.5Fisk | 954Fisk 1049Fisk | 116Fisk; 20 °C | 20.5Fisk; 20 to 300 °C |
| Cartridge brass 70/30 (UNS C26000) | 8.53Aviva; 20 °C | 916Aviva 954Aviva | 121.2Aviva; 20 °C | 20Aviva; 20 to 300 °C |
| Leaded free-machining brass CW614N (CuZn39Pb3, UNS C38500) | 8.46HME; 20 °C 8.47Brassland; 20 °C 8.44Alumeco; 20 °C | 875 to 890HME 877 to 888Brassland | 123HME | 21.4HME |
| Copper (oxygen-free grade C10200) | 8.9Aurubis 8.96PubChem; copper, CAS 7440-50-8, 25 °C | 1083Aurubis 1084.62PubChem; copper, CAS 7440-50-8 | 391Aurubis; 20 °C 547NIST; 77 K | 17.6Aurubis; 20 °C |
4
How much electrical conductivity does alloying take away from copper?
Alloying costs conductivity: oxygen-free copper prints 58 MS/m, which the datasheet equates to 100 %IACS (per Aurubis, soft), while the 11 alloys here print 5 to 30 %IACS, from cupronickel UNS C71500 (5) to beryllium copper UNS C17200 (25 to 30). Each value is for the temper or temperature its source states.
%IACS is electrical conductivity as a percentage of the International Annealed Copper Standard, where annealed pure copper is 100. Bars start at zero. Each row is one source's value for the stated condition; a range is drawn solid to its lower value and hatched to its upper.
| Alloy | Conductivity, %IACS | Bar, 0 to 100 %IACS | Condition | Source |
|---|---|---|---|---|
| Copper (oxygen-free grade C10200) | 58 MS/m, printed as equal to 100 %IACS | soft | Aurubis | |
| Beryllium copper (UNS C17200) | 25 to 30 | precipitation age-hardened (heat treated) | Materion | |
| Cartridge brass 70/30 (UNS C26000) | 28 | 68 °F (20 °C) | Aviva | |
| Free-cutting brass UNS C36000 | 26 | H02, 1/2 hard | Aviva | |
| Leaded free-machining brass CW614N (CuZn39Pb3, UNS C38500) | 25 | not stated | HME | |
| Phosphor bronze UNS C51000 (CuSn5P) | 15 | 68 °F (20 °C) | Concast | |
| Phosphor bronze UNS C52100 (CuSn8) | 13 | 68 °F (20 °C) | Concast | |
| Aluminium bronze UNS C95400 | 13 | 68 °F (20 °C) | Concast | |
| Aluminium bronze UNS C63000 (wrought, CuAl10Ni5Fe4) | 7 | 68 °F (20 °C) | National Bronze | |
| Silicon bronze UNS C65500 (CuSi3Mn1) | 7 | 68 degF (20 degC) | Austral Wright | |
| Nickel silver UNS C75200 | 6 | annealed | Fisk | |
| Cupronickel 70/30 (UNS C71500) | 5 | 68 ºF as printed (about 20 °C) | Wieland |
5
Is brass a bronze, and is beryllium copper a bronze?
No. Brass is copper with zinc as the main ingredient: UNS C36000, UNS C26000 and UNS C38500 print zinc as the balance. Bronze is copper with tin, aluminium, silicon or another main ingredient, and 3 of the 5 bronze profiles print zinc only as a maximum of 0.20 to 1.5 wt%. Beryllium copper UNS C17200 is a copper alloy, not named a bronze in its profile.
The Space Mushroom copper-alloys description counts brasses as copper and zinc, and bronzes as copper with tin, aluminium or other elements. The name follows the main ingredient, not the strength. Nickel silver UNS C75200 is copper with nickel and zinc, and its printed formula lists no silver. Cupronickel UNS C71500 is copper with 29.0 to 33.0 % nickel.
6
What does our data not say about what bronze is made of?
Not found in any source we hold: a typical analysis as opposed to a limit for any alloy here, and a hardness comparable across alloys. Hardness is held under Brinell (2 profiles), Rockwell B (1 profile) and Vickers (3 profiles) scales that cannot be converted, so this page does not compare it.
- Every composition here is a printed limit or a nominal value from a supplier or standard, not a measured analysis of a delivered batch.
- Where two sources print different limits for one grade, both rows are shown and neither is averaged: nickel silver (Fisk C752 against Matthey CW409J), free-cutting brass lead (Aviva and Fisk against Wikipedia), and the copper row of cupronickel.
- The effect of a single ingredient is shown only where two profiles share a temper and a data sheet. Anything else would mix conditions, so it is left out.
- Beryllium copper is not named a bronze in its profile. That it is sold as a copper alloy rather than as a bronze is general engineering knowledge, not in our data.
7
Questions people ask about what bronze is made of
What is bronze made of?
Bronze is made of copper plus a second main ingredient. Our data shows tin in phosphor bronze UNS C52100 (7.00 to 9.00 wt% tin, per Concast), aluminium in aluminium bronze UNS C63000 (9.0 to 11.0 wt% aluminium, per National Bronze) and silicon in silicon bronze UNS C65500 (2.8 to 3.8 wt% silicon, per Austral Wright). Copper is the base of each.
What is phosphor bronze made of?
Phosphor bronze UNS C52100 (CuSn8) is copper with 7.00 to 9.00 wt% tin and 0.03 to 0.35 wt% phosphorus (per Concast), and Phosphor bronze UNS C51000 (CuSn5P) is copper with 4.20 to 5.80 wt% tin and 0.03 to 0.35 wt% phosphorus (per Concast). Both cap lead at 0.05 wt% and iron at 0.10 wt%; zinc is capped at 0.30 wt% in UNS C51000 and 0.20 wt% in UNS C52100.
What is aluminium bronze made of?
Aluminium bronze UNS C63000 (wrought, CuAl10Ni5Fe4) is copper with 9.0 to 11.0 wt% aluminium, 4.0 to 5.5 wt% nickel and 2.0 to 4.0 wt% iron and at most 1.5 wt% manganese (per National Bronze). Aluminium bronze UNS C95400, a casting alloy, is copper with 10.00 to 11.50 wt% aluminium and 3.00 to 5.00 wt% iron, and caps nickel at 1.50 wt% (per Concast).
What is silicon bronze made of?
Silicon bronze UNS C65500 (CuSi3Mn1) is a wrought copper alloy with 2.8 to 3.8 wt% silicon and 0.50 to 1.3 wt% manganese (per Austral Wright). It prints caps for iron (0.8 wt%), zinc (1.5 wt%), nickel (0.6 wt%) and lead (0.05 wt%). Copper is the matrix, and its profile also lists the trade names Everdur and Cusilman.
Does all bronze contain tin?
No. Only 2 of the 5 bronze profiles in our data print tin as an ingredient: UNS C51000 and UNS C52100. The aluminium bronzes UNS C63000 and UNS C95400 and the silicon bronze UNS C65500 print no tin at all. The word bronze covers copper alloys with tin, aluminium, silicon or other main ingredients.
Is beryllium copper a bronze?
Beryllium copper UNS C17200 is described in its profile as a copper alloy with 1.80 to 2.00 wt% beryllium (per Materion), and our data does not call it a bronze. General engineering knowledge, not in our data: it is sold under the name beryllium copper, and some catalogues call it beryllium bronze.
What is the difference between bronze and brass?
Bronze takes tin, aluminium or silicon as its main ingredient; brass takes zinc. In our data, brass UNS C36000 prints 60.0 to 63.0 wt% copper with zinc as the balance (per Aviva), while 3 of 5 bronzes cap zinc at 0.20 to 1.5 wt%. Brasses UNS C36000 and UNS C38500 also add 2.5 to 3.0 and 2.5 to 3.5 wt% lead.
Does bronze contain lead?
Not as an addition in the bronzes we hold. Lead appears there only as a maximum of 0.05 wt% (UNS C51000, UNS C52100, UNS C63000 and UNS C65500). The free-cutting brass UNS C36000 prints 2.5 to 3.0 wt% lead (per Aviva) and leaded brass UNS C38500 prints 2.5 to 3.5 wt% (per HME), so lead is a brass ingredient in our data.
Related on Space Mushroom
- Density and hardness of copper alloys: brass, bronze, copper-nickel and beryllium copper
- Brass vs bronze vs copper: strength, conductivity, corrosion
- Brass vs bronze: properties compared
- Copper vs bronze: properties compared
- Copper alloys: the full collection
- Phosphor bronze UNS C51000 (CuSn5P): profile and sources
- Phosphor bronze UNS C52100 (CuSn8): profile and sources
- Aluminium bronze UNS C63000 (wrought, CuAl10Ni5Fe4): profile and sources
- Aluminium bronze UNS C95400: profile and sources
- Silicon bronze UNS C65500 (CuSi3Mn1): profile and sources
- Beryllium copper (UNS C17200): profile and sources
- Cupronickel 70/30 (UNS C71500): profile and sources
- Nickel silver UNS C75200: profile and sources
- Free-cutting brass UNS C36000: profile and sources
- Cartridge brass 70/30 (UNS C26000): profile and sources
- Leaded free-machining brass CW614N (CuZn39Pb3, UNS C38500): profile and sources
- Copper (oxygen-free grade C10200): profile and sources
How this was made
Each alloy is a profile in the Space Mushroom database. The profiles are drafted by AI assistants from the cited pages, and a script checks that every value appears in the source it cites; each profile page lists its sources. The composition limits on this page are parsed from the profile's printed formula text, and the build stops if a phrase is no longer found there. Nothing on the page comes from memory.
Data checked 2 November 2026. Next review when a profile changes.
How to cite: Space Mushroom, "What is bronze made of? Tin, aluminium, silicon and beryllium bronzes", https://spacemushroom.com/articles/what-is-bronze-made-of/, data checked 2 November 2026.