Phosphor bronze C51000 (CuSn5P) C510
Cu-Sn-P wrought alloy, UNS C51000: copper remainder (93.6 to 95.6 %), tin 4.20 to 5.80 %, phosphorus 0.03 to 0.35 %
Also known as UNS C51000, EN name CW451K, EN name CuSn5, SAE J461, SAE J463, BS PB102 · 9 more
Phosphor bronze C51000 (UNS C51000, EN CW451K, name CuSn5, also sold as phosphor bronze 5% A) is a wrought copper alloy with 4.20 to 5.80 % tin and 0.03 to 0.35 % phosphorus.
Evidence level
2 of 5
Lab-measured
- 0Predicted only. No one has made it, or no measurement exists.
- 1Calculated. Only calculated or predicted values from sources.
- 2Lab-measured. Measured properties with their conditions stated.
- 3Space-relevant tests. Measured in conditions relevant to space, such as vacuum or atomic oxygen.
- 4Ground-qualified. Qualified for an application on the ground.
- 5Flown or field-proven. Flight or field results exist.
Carry springs
790 MPa minimum
Take the density
8.86 g/cm3
Conduct electricity
15 %IACS
Melt
954 to 1049 °C
Recipe, share of the weight
- Cu not statedCopper
- Sn not statedTin
- P not statedPhosphorus
- Pb not statedLead
- Zn not statedZinc
- Fe not statedIron
Best for
Springs and electrical contacts: H08 spring temper has a minimum tensile strength of 790 MPa in fine round sizes (Concast), and the alloy solders and brazes well
Weakest at
Dust and fume when cut, ground or welded (Fisk SDS); a seawater corrosion rate for C51000 was not found in this run
Risk at a glance
- People Low. Dust and fume, not solid metal
- If it fails Moderate. Fatigue under reversed bending
- Corrosion Low. The wire datasheet rates corrosion resistance as good to excellent, with no numeric rate.
Quick facts: C510
| Property | Value | Basis |
|---|---|---|
| Density | 8.86 g/cm³ | 1 sourced value |
| Yield strength | 550 MPa | 1 sourced value |
| Tensile strength | 485 to 790 MPa | 4 sourced values across conditions |
| Young's modulus | 110 GPa | 1 sourced value |
| Thermal conductivity | 84 W/(m·K) | 1 sourced value |
| Thermal expansion (CTE) | 17.8 ppm/K | 1 sourced value |
| Melting point | 954 to 1,049 °C | 1 sourced value |
| Specific heat | 380 J/(kg·K) | 1 sourced value |
| Electrical resistivity | 8.7e-8 Ω·m | 1 sourced value |
What is the density of Phosphor bronze C51000 (CuSn5P)?
Phosphor bronze C51000 (CuSn5P) has a density of 8.86 g/cm³. The source and test conditions are listed in the properties table on this page.
What is the thermal conductivity of Phosphor bronze C51000 (CuSn5P)?
Phosphor bronze C51000 (CuSn5P) has a thermal conductivity of 84 W/(m·K). The source and test conditions are listed in the properties table on this page.
What is the coefficient of thermal expansion of Phosphor bronze C51000 (CuSn5P)?
Phosphor bronze C51000 (CuSn5P) has a coefficient of thermal expansion of 17.8 ppm/K. The source and test conditions are listed in the properties table on this page.
What is the melting point of Phosphor bronze C51000 (CuSn5P)?
Phosphor bronze C51000 (CuSn5P) has a melting point of 954 to 1,049 °C. The source and test conditions are listed in the properties table on this page.
What is the yield strength of Phosphor bronze C51000 (CuSn5P)?
Phosphor bronze C51000 (CuSn5P) has a yield strength of 550 MPa. The source and test conditions are listed in the properties table on this page.
What are the other names and codes for Phosphor bronze C51000 (CuSn5P)?
Phosphor bronze C51000 (CuSn5P) is also written as UNS C51000, EN name CW451K, EN name CuSn5, SAE J461, SAE J463, BS PB102. Each code is printed in the source listed beside it in the designations table.
What is Phosphor bronze C51000 (CuSn5P) used for?
Uses recorded in the sources include Electrical contacts and wire forms; Springs, bushings and bearings; Fasteners.
Why it exists
Phosphor bronze C51000 is a copper alloy with about 5 % tin and 0.2 % phosphorus. Tin gives it corrosion resistance and strength, and phosphorus adds wear resistance and stiffness. The Concast C51000 page gives a minimum tensile strength of 485 MPa for H04 hard bar and 790 MPa for H08 spring in fine round sizes. The Sullins H02 wire datasheet gives 585 MPa tensile and 550 MPa yield at 0.5 % extension. The alloy is used for springs, electrical contacts and fasteners.
Where it's used
Electrical contacts
Sullins sells the H02 wire as a contact material, and Wikipedia says phosphor bronze wire is suited to springs, electrical contacts and wire forms where beryllium copper is not required.
Springs and bushings
Wikipedia lists springs, bolts, bushings and bearings among phosphor bronze applications. The H08 spring temper has a minimum tensile strength of 790 MPa in fine round sizes.
Fasteners
Concast lists fasteners among the typical uses of C51000 and sells it as bar, rod and wire.
Recipe
Cu-Sn-P wrought alloy, UNS C51000: copper remainder (93.6 to 95.6 %), tin 4.20 to 5.80 %, phosphorus 0.03 to 0.35 %; lead 0.05 max, zinc 0.30 max, iron 0.10 max (wt %)
C51000 is a copper-tin-phosphorus alloy: copper is the matrix, and tin gives most of the strength and corrosion resistance. Phosphorus is a trace addition that Wikipedia says raises wear resistance and stiffness. Lead, zinc and iron are impurity limits, and the wrought bar, rod, wire and sheet are made by cold working and annealing.
| Ingredient | Share of the weight | What it does |
|---|---|---|
| Copper Cu | not stated | The matrix. The Sullins datasheet gives Cu 93.6 to 95.6 %; the Concast page gives copper as the remainder. |
| Tin Sn | not stated | Gives most of the strength and corrosion resistance (Wikipedia, Concast composition table). |
| Phosphorus P | not stated | A trace addition that raises wear resistance and stiffness (Wikipedia). |
| Lead Pb | not stated | Impurity limit. |
| Zinc Zn | not stated | Impurity limit. |
| Iron Fe | not stated | Impurity limit. |
Weight shares are as printed in the sources.
What it can do
Carry springs
790 MPa minimum
measured
The H08 spring temper has a minimum tensile strength of 790 MPa for 0.026 inch to 1/16 inch round wire.
Take the density
8.86 g/cm3
measured
The Sullins datasheet gives a density of 8.86 g/cm3 at 20 °C.
Conduct electricity
15 %IACS
measured
The Concast page gives an electrical conductivity of 15 %IACS at 68 °F, for an alloy with 5 % tin and 0.2 % phosphorus.
Melt
954 to 1049 °C
measured
The solidus is 954 °C and the liquidus is 1049 °C in the Concast table. The Sullins sheet gives a different range.
How it compares
Compared with pure copper, the phosphor bronze C51000 gives much higher strength in the spring temper, and the datasheets give 15 %IACS electrical conductivity for the alloy. Compare the three rows below as examples; the copper profile uses a different grade.
The same measurements for each material, so you can compare them. Each row names the key condition under the value; the full conditions and methods are in the numbered notes under Technical details. Other materials are shown beside it; each was measured under its own conditions, so open its page before comparing closely. Compare every grade in the family.
| Measurement | C510 | Cu | C360 | C954 | C630 | BeCu | C260 | Cu-Ag | CuCrZr | CuNi 70/30 | C21000 | CW614N | C75200 | C521 | C655 | Cu-Te | Sn/Cu |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Thermal behavior and safety | |||||||||||||||||
| Solidus and liquidus, phosphor bronze C51000 | 954 to 1049 °C2 | 1083 °C | 954 °C | 1027 °C | 1060 °C | 870 °C | 916 °C | no data | 1081 °C | 1170 to 1240 °C | 954 °C | 875 to 890 °C | 1060 to 1110 °C | 882 to 1027 °C | 971 to 1027 °C | 1080 °C | 231.9 °C |
| Thermal conductivity at 20 °C, phosphor bronze C51000 wireValue printed in a supplier wire datasheet | 84 W/(m·K)4 | 391 W/(m·K) | 116 W/(m·K) | 58.7 W/(m·K) | 63 W/(m·K) | 105 W/(m·K) | 121.2 W/(m·K) | no data | 323 W/(m·K) | 29 W/(m·K) | 234 W/(m·K) | 123 W/(m·K) | 32 W/(m·K) | 67 W/(m·K) | 36.3 W/(m.K) | 355 W/(m·K) | 66.6 W/(m·K) |
| Specific heat capacity, phosphor bronze C51000 wireValue printed in a supplier wire datasheet | 0.38 J/(g·°C)6 | 0.394 kJ/(kg·K) | no data | 419 J/(kg·K) | 452 J/(kg·K) | no data | 377.1 J/(kg·K) | no data | 0.383 kJ/(kg·K) | 377 J/(kg·K) | 0.38 J/(g·K) | 380 J/(kg·K) | 380 J/(kg·K) | 0.377 kJ/(kg·K) | 376.8 J/(kg.K) | 385.5 J/(kg·K) | no data |
| Physical and electrical | |||||||||||||||||
| Density, phosphor bronze C51000Value printed in a supplier wire datasheet | 8.86 g/cm³1 | 8.9 g/cm³ | 8.5 g/cm³ | 7.45 g/cm³ | 7.58 g/cm³ | 8.36 g/cm³ | 8.53 g/cm³ | no data | 8.94 g/cm³ | 8.94 g/cm³ | 8.86 g/cm³ | 8.46 g/cm³ | 8.7 g/cm³ | 8.79 g/cm³ | 8.53 g/cm³ | 8.94 g/cm³ | 7.28 g/cm³ |
| Electrical conductivity, phosphor bronze C51000 | 15 %IACS3 | 58 MS/m | 26 %IACS | 13 %IACS | 7 %IACS | 25 to 30 %IACS | 28 %IACS | > 58 MS/m | > 46.4 MS/m | no data | 56 %IACS | 25 %IACS | 6 %IACS | 13 %IACS | 7 %IACS | 93 %IACS | 58 MS/m |
| Electrical resistivity at 20 °C, phosphor bronze C51000 wireValue printed in a supplier wire datasheet | 8.7×10^-6 ohm·cm8 | no data | 6.63 µΩ·cm | 13.33 µΩ·cm | 0.172 µΩ·m | 5.8 to 6.9 μΩ-cm | 6.15 µΩ·cm | no data | no data | 37.4 µΩ·cm | 3.08 µΩ·cm | no data | no data | no data | 24.6 microohm-cm | no data | 11.5 µΩ·cm |
| Other measurements | |||||||||||||||||
| Coefficient of linear thermal expansion, 20 to 300 °CValue printed in a supplier wire datasheet | 17.8 µm/(m·°C)5 | 17.6 ppm/K | 20.5 ppm/K | 16.2 ppm/K | 15 ppm/K | 17.5 ppm/K | 20 ppm/K | no data | 17.1 ppm/K | 13.2 to 16.2 ppm/K | 18 ppm/K | 21.4 ppm/K | 17.7 ppm/K | 17.4 µm/(m·°C) | 18 um/(m.°C) | 16.5 ppm/K | 22 ppm/K |
| Modulus of elasticity, phosphor bronze C51000 wireValue printed in a supplier wire datasheet | 110 GPa7 | 117 GPa | no data | 1.07×10^5 MPa | 117 GPa | 131 GPa | 1.1×10^5 MPa | no data | 117 GPa | no data | 117 GPa | 97 GPa | 135 GPa | 115 GPa | 1.03×10^5 MPa | 1.17×10^5 MPa | 50 GPa |
| Tensile strength, H04 hard temper, minimum | > 485 MPa9 | 179 to 262 MPa | > 330 MPa | > 586 MPa | > 585 MPa | 410 to 590 MPa | 324 MPa | 180 N/mm2 | 480 to 560 MPa | 358 to 414 MPa | 235 MPa | > 360 MPa | 370 to 430 MPa | 475 to 580 MPa | 538 MPa | > 260 MPa | no data |
| Elongation, H04 hard temper, minimum | > 13 %10 | 35 % | > 15 % | > 12 % | > 10 % | 20 to 75 % | 62 % | > 37 % | > 10 % | 30 to 45 % | 45 % | > 20 % | 40 % | > 25 % | 17 % | > 8 % | no data |
| Tensile strength, H08 spring temper, minimum | > 790 MPa11 | 179 to 262 MPa | > 330 MPa | > 586 MPa | > 585 MPa | 410 to 590 MPa | 324 MPa | 180 N/mm2 | 480 to 560 MPa | 358 to 414 MPa | 235 MPa | > 360 MPa | 370 to 430 MPa | 475 to 580 MPa | 538 MPa | > 260 MPa | no data |
| Tensile strength, H02 wireValue printed in a supplier wire datasheet | 585 MPa12 | 179 to 262 MPa | > 330 MPa | > 586 MPa | > 585 MPa | 410 to 590 MPa | 324 MPa | 180 N/mm2 | 480 to 560 MPa | 358 to 414 MPa | 235 MPa | > 360 MPa | 370 to 430 MPa | 475 to 580 MPa | 538 MPa | > 260 MPa | no data |
| Yield strength at 0.5 % extension, H02 wireValue printed in a supplier wire datasheet | 550 MPa13 | 69 MPa | > 130 MPa | > 221 MPa | > 295 MPa | 130 to 250 MPa | 103 MPa | no data | > 450 MPa | 124 to 179 MPa | no data | > 220 MPa | no data | > 350 MPa | 310 MPa | > 205 MPa | no data |
| Elongation at break, H02 wireValue printed in a supplier wire datasheet | 8 %14 | 35 % | > 15 % | > 12 % | > 10 % | 20 to 75 % | 62 % | > 37 % | > 10 % | 30 to 45 % | 45 % | > 20 % | 40 % | > 25 % | 17 % | > 8 % | no data |
| Ultimate tensile strength, hard temper sheet (France et al. 1969 data) | 607 MPa15 | 179 to 262 MPa | > 330 MPa | > 586 MPa | > 585 MPa | 410 to 590 MPa | 324 MPa | 180 N/mm2 | 480 to 560 MPa | 358 to 414 MPa | 235 MPa | > 360 MPa | 370 to 430 MPa | 475 to 580 MPa | 538 MPa | > 260 MPa | no data |
| Elongation, hard temper sheet (France et al. 1969 data) | 9 %16 | 35 % | > 15 % | > 12 % | > 10 % | 20 to 75 % | 62 % | > 37 % | > 10 % | 30 to 45 % | 45 % | > 20 % | 40 % | > 25 % | 17 % | > 8 % | no data |
Why choose it, and why not
Good for
- Springs and electrical contacts: H08 spring temper gives 790 MPa minimum tensile strength in fine round sizes.
- Solderable and brazeable parts: the Concast fabrication table rates soldering and brazing as excellent.
- Fasteners and bushings: wear resistance is raised by phosphorus, according to Wikipedia.
Watch out for
- Dust and fume when cut, ground or welded, per the Fisk SDS.
- Strength falls if the part is annealed above 475 °C.
- No seawater corrosion rate for C51000 was found in this run.
- Melting ranges differ between the Concast and Sullins sources.
Phosphor bronze C51000 is a tin-bronze with 4.20 to 5.80 % tin and 0.03 to 0.35 % phosphorus. Its strength depends strongly on temper, and the H08 spring temper gives 790 MPa minimum tensile strength in fine round sizes. The alloy is solderable and brazeable, and dust from machining is the main hazard. This profile lacks a seawater corrosion rate and the W.Nr. number.
Technical details
For scientists and researchers. Everything above comes from the record below: every number with its method, its conditions and its source.
Other names and standards
The same grade under other systems, as datasheets and standards print them. Each code was checked against the page it comes from.
| System | Codes |
|---|---|
| UNS | C51000 |
| EN name | CW451K, CuSn5 |
| SAE | J461, J463 |
| BS | PB102 |
| CDA | C510 |
| ISO | CuSn5 |
| ASTM | B139 (bar and rod), B103 (bar, plate, sheet and strip), B159 (wire) |
| AMS | 4625 (bar, rod and tube), 4510 (plate, sheet and strip), 4720 (wire) |
| Trade name | Phosphor bronze 5% A |
Notes
The method, full conditions and any caveat for the numbered rows above.
| # | Measurement | Method | Conditions | Caveat |
|---|---|---|---|---|
| 1 | Density, phosphor bronze C51000 | — | grade C51000 (5 % Sn, 0.2 % P)temperature 20 °Cunit in source 0.32 lb/in3 at 68 °F | — |
| 2 | Solidus and liquidus, phosphor bronze C51000 | Solidus and liquidus printed in the physical properties table of a supplier page; value is the solidus (low) and the liquidus (high) | grade C51000unit in source solidus 1750 °F; liquidus 1920 °Fpressure not stated | The Sullins wire datasheet prints a different range, solidus 975 °C and liquidus 1060 °C, for the same alloy. Both are recorded in the sources; this entry uses the Concast figures. |
| 3 | Electrical conductivity, phosphor bronze C51000 | Value printed in the physical properties table of a supplier page | grade C51000temperature 68 °F (20 °C)footnote Determined on an alloy containing 5 % tin and 0.2 % phosphorus | — |
| 4 | Thermal conductivity at 20 °C, phosphor bronze C51000 wire | — | form wire, 2 mm diametertemperature 20 °Cunit in source 583 BTU-in/hr-ft2-°F | The Concast physical properties table gives 40 Btu/sq ft/ft hr/°F at 68 °F in US units only; that value is not converted here and is not entered as a property. |
| 5 | Coefficient of linear thermal expansion, 20 to 300 °C | — | temperature range 20 to 300 °C (68 to 570 °F)unit in source 9.89 µin/in-°F | The Sullins table row is labelled 250 °C, but the range printed in the same cell is 20 to 300 °C, so the range is recorded as printed. |
| 6 | Specific heat capacity, phosphor bronze C51000 wire | — | form wiretemperature not statedunit in source 0.0908 BTU/lb-°F | — |
| 7 | Modulus of elasticity, phosphor bronze C51000 wire | — | form wiretemperature not statedunit in source 16000 ksi | — |
| 8 | Electrical resistivity at 20 °C, phosphor bronze C51000 wire | — | form wiretemperature 20 °Cunit in source 8.7e-006 ohm-cm | — |
| 9 | Tensile strength, H04 hard temper, minimum | Minimum value printed in a mechanical properties table of a supplier page | temper H04 hardsize 1/4 to 1/2 inch round and hexagonalunit in source 70 ksistandard ASTM B139 | — |
| 10 | Elongation, H04 hard temper, minimum | Minimum value printed in a mechanical properties table of a supplier page | temper H04 hardsize 1/4 to 1/2 inch round and hexagonalbasis 4 times diameter or specimen thickness | — |
| 11 | Tensile strength, H08 spring temper, minimum | Minimum value printed in a mechanical properties table of a supplier page | temper H08 springsize 0.026 inch to 1/16 inch roundunit in source 115 ksistandard ASTM B139 | — |
| 12 | Tensile strength, H02 wire | — | temper H02form wire, 2 mm diameterunit in source 84800 psielongation gauge 50 mm | — |
| 13 | Yield strength at 0.5 % extension, H02 wire | — | temper H02form wire, 2 mm diametermeasure 0.5 % extension under loadunit in source 79800 psi | — |
| 14 | Elongation at break, H02 wire | — | temper H02form wire, 2 mm diametergauge length 50 mm | — |
| 15 | Ultimate tensile strength, hard temper sheet (France et al. 1969 data) | Value in the data file of a University of Waterloo materials page, which cites W.D. France et al., ASTM Journal of Materials, 1969; the source notes the data were digitised from plots and may contain errors | temper hard, made by three roll and anneal cycles then a final roll to 0.040 inchform sheetunit in source 88 ksi | — |
| 16 | Elongation, hard temper sheet (France et al. 1969 data) | Value in the data file of a University of Waterloo materials page; digitised from plots | temper hardform sheetgauge length 2 inch | — |
Corrosion and compatibility
What happens when it meets other materials and environments.
| Environment | Concern | What happens |
|---|---|---|
| Air and general service, rated qualitatively | low | The wire datasheet rates corrosion resistance as good to excellent, with no numeric rate.1 |
| Alloy chemistry, tin content | low | Tin is the element that gives phosphor bronze its corrosion resistance.2 |
| # | Environment | Details | Test conditions |
|---|---|---|---|
| 1 | Air and general service, rated qualitatively | The Sullins material notes say the alloy has good to excellent corrosion resistance. No corrosion rate in mm/year or mpy was printed on any page read in this run. | basis qualitative statement from a wire datasheetexposure not stated |
| 2 | Alloy chemistry, tin content | Wikipedia says tin raises the corrosion resistance and strength of phosphor bronze, and that phosphorus raises wear resistance and stiffness. The article gives no corrosion data. | basis general description, no test data |
Risks and side effects
Hazards to people, what happens when a cell overheats, and how the material is handled and stored.
For people
The opened sources give a hazard for dust and fume from the alloy, not for the solid metal.
- Solid alloy
- The Fisk SDS classifies the solid alloy as Not Classified under GHS-US, with no labelling. Hazards come from the dust, fume and powder made when it is cut, ground or welded.
- Tin and phosphorus in dust
- The same SDS says tin dust and fume can cause stannosis after chronic exposure and that tin has been shown to increase sarcoma incidence in animal tests. It also says long-term phosphorus exposure may affect the kidney and liver.
If it fails
The failure routes in the sources are fatigue in hard temper sheet and loss of temper on annealing.
- Fatigue
- In the digitised 1969 data, hard temper sheet failed at 618,640 reversals at 337 MPa stress amplitude, and samples at 174 to 182 MPa reached runout at 200,000,000 reversals.
- Annealing
- The Sullins datasheet gives an annealing range of 475 to 675 °C. Heating into it resets the temper.
Handling and storage
- Specify the temper
- H04 hard has 485 MPa minimum tensile strength, H08 spring has 790 MPa minimum in fine round sizes, and H02 wire has 550 MPa yield. Choose the temper before the strength is quoted.
- Dust
- Control dust, fume and sparks when cutting, grinding or welding.
Test details
The original wording and numbers from the sources, for readers who want them.
Failure risks
| Failure | Trigger and consequence |
|---|---|
| Fatigue under reversed bendingmoderate severity | Cyclic bending of hard temper sheet at stress amplitudes of about 170 to 340 MPaIn the digitised data, the sample with a stress amplitude of 337 MPa failed at 618,640 reversals, and the runout samples at 174 to 182 MPa survived 200,000,000 reversals without failure. |
| Loss of the set temper on annealingmoderate severity | Heating into the annealing range of 475 to 675 °CThe temper is reset, so the H02, H04 or H08 strength values stop applying to the part. |
Handling and storage
- Specify the temper, since H04 hard, H08 spring and H02 wire have very different strengths, from 485 MPa minimum for H04 to 790 MPa minimum for H08 in fine round sizes.
- Keep parts out of the annealing range of 475 to 675 °C unless the temper is to be reset.
- Control dust, fume and sparks when cutting, grinding or welding, since the SDS warns of irritation and a combustible dust hazard.
Supply and geography
How common the raw materials are and where they come from.
Copper (93.6 to 95.6 % of the alloy)
- Top producers (2025)
- Chile 23%, Congo (Kinshasa) 13.9%, Peru 11.7%, China 7.8%, Russia 5.7%
- Critical mineral lists
- U.S. Final 2025 List of Critical Minerals (copper added, 90 FR 50494): listed
- Substitutes
- USGS: aluminum substitutes for copper in electrical equipment and power cable, and optical fiber substitutes for copper in telecommunications applications.
Tin (4.20 to 5.80 % of the alloy)
- Top producers (2025)
- China 24.5%, Indonesia 21%, Peru 11.4%, Brazil 9.7%, Congo (Kinshasa) 9.3%
- Recycling
- USGS: about 17,000 tons of tin from old and new scrap was recycled in 2025, of which about 10,000 tons came from old scrap, and the scrap supplied 22 % of apparent consumption.
- Substitutes
- USGS: aluminum, glass, paper, plastic or tin-free steel substitute for tin in cans and containers; epoxy resins substitute for tin in solder.
Documents
Datasheets, safety data sheets, papers and standards you can open.
Full record
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spore: profile
id: bronze-c510
spore_version: 0.2
family: copper-alloys
name: Phosphor bronze C51000 (CuSn5P)
abbreviation: C510
role: wrought copper-tin alloy for springs, electrical contacts and fasteners
category: metals
type: copper-alloys
summary: |
Phosphor bronze C51000 (UNS C51000, EN CW451K, name CuSn5, also sold as phosphor bronze 5% A) is a wrought copper alloy with 4.20 to 5.80 % tin and 0.03 to 0.35 % phosphorus. Its density is 8.86 g/cm3 and its electrical conductivity is 15 %IACS. The spring temper H08 has a minimum tensile strength of 790 MPa in fine round sizes, and H02 wire has a yield strength of 550 MPa. It is sold for springs, electrical contacts and fasteners.
best_for: 'Springs and electrical contacts: H08 spring temper has a minimum tensile strength of 790 MPa in fine round sizes (Concast), and the alloy solders and brazes well'
weakest_at: Dust and fume when cut, ground or welded (Fisk SDS); a seawater corrosion rate for C51000 was not found in this run
identity:
formula: 'Cu-Sn-P wrought alloy, UNS C51000: copper remainder (93.6 to 95.6 %), tin 4.20 to 5.80 %, phosphorus 0.03 to 0.35 %; lead 0.05 max, zinc 0.30 max, iron 0.10 max (wt %)'
source: concast-c51000
where: Chemical composition table, C51000 section (concast.com); the aircraftmaterials.com composition table prints the same tin, phosphorus, lead, zinc and iron limits; the Sullins datasheet gives copper 93.6 to 95.6
designations:
- system: UNS
code: C51000
source: aircraftmaterials-cda510
where: Page title
- system: CDA
code: C510
source: concast-c51000
where: Sentence C510 is also designated as CuSn5, CW451K, and PB102
- system: EN name
code: CW451K
source: concast-c51000
where: Same sentence as the C510 designation
- system: EN name
code: CuSn5
source: concast-c51000
where: Same sentence as the C510 designation
- system: BS
code: PB102
source: concast-c51000
where: Same sentence as the C510 designation
- system: ISO
code: CuSn5
source: sullins-ca510
where: Key Words line, ISO CuSn5
- system: ASTM
code: B139
note: bar and rod
source: aircraftmaterials-cda510
where: Specifications table, Bar and Rod row
- system: ASTM
code: B103
note: bar, plate, sheet and strip
source: aircraftmaterials-cda510
where: Specifications table, Bar, Plate, Sheet and Strip row
- system: ASTM
code: B159
note: wire
source: aircraftmaterials-cda510
where: Specifications table, Wire row
- system: SAE
code: J461
source: aircraftmaterials-cda510
where: Specifications table, Rod, Sheet, Strip and Wire row
- system: SAE
code: J463
source: aircraftmaterials-cda510
where: Specifications table, Rod, Sheet, Strip and Wire row
- system: AMS
code: '4625'
note: bar, rod and tube
source: aircraftmaterials-cda510
where: Specifications table, Bar, Rod and Tube row
- system: AMS
code: '4510'
note: plate, sheet and strip
source: aircraftmaterials-cda510
where: Specifications table, Plate, Sheet and Strip row
- system: AMS
code: '4720'
note: wire
source: aircraftmaterials-cda510
where: Specifications table, Wire row
- system: Trade name
code: Phosphor bronze 5% A
source: concast-c51000
where: Product overview, product description
tags:
environments: []
stresses: []
applications:
- electronics-and-chips
- mechanisms
- structures
properties:
- benchmark: density
label: Density, phosphor bronze C51000
value: 8.86
unit: g/cm3
scope: material
conditions:
grade: C51000 (5 % Sn, 0.2 % P)
temperature: 20 °C
unit_in_source: 0.32 lb/in3 at 68 °F
method: Value printed in a supplier wire datasheet
status: ground
source: sullins-ca510
where: Physical Properties table, row Density (page 1)
- benchmark: melting_point
label: Solidus and liquidus, phosphor bronze C51000
value: 954
value_high: 1049
bound: range
unit: °C
scope: material
conditions:
grade: C51000
unit_in_source: solidus 1750 °F; liquidus 1920 °F
pressure: not stated
method: Solidus and liquidus printed in the physical properties table of a supplier page; value is the solidus (low) and the liquidus (high)
status: ground
note: The Sullins wire datasheet prints a different range, solidus 975 °C and liquidus 1060 °C, for the same alloy. Both are recorded in the sources; this entry uses the Concast figures.
source: concast-c51000
where: Physical properties table, rows Melting point liquidus and solidus
- benchmark: electrical_conductivity
label: Electrical conductivity, phosphor bronze C51000
value: 15
unit: '%IACS'
scope: material
conditions:
grade: C51000
temperature: 68 °F (20 °C)
footnote: Determined on an alloy containing 5 % tin and 0.2 % phosphorus
method: Value printed in the physical properties table of a supplier page
status: ground
source: concast-c51000
where: Physical properties table, row Electrical conductivity
- benchmark: thermal_conductivity
label: Thermal conductivity at 20 °C, phosphor bronze C51000 wire
value: 84
unit: W/(m·K)
scope: material
conditions:
form: wire, 2 mm diameter
temperature: 20 °C
unit_in_source: 583 BTU-in/hr-ft2-°F
method: Value printed in a supplier wire datasheet
status: ground
note: The Concast physical properties table gives 40 Btu/sq ft/ft hr/°F at 68 °F in US units only; that value is not converted here and is not entered as a property.
source: sullins-ca510
where: Physical Properties table, page 2, row Thermal Conductivity
- benchmark: cte
label: Coefficient of linear thermal expansion, 20 to 300 °C
value: 17.8
unit: µm/(m·°C)
scope: material
conditions:
temperature_range: 20 to 300 °C (68 to 570 °F)
unit_in_source: 9.89 µin/in-°F
method: Value printed in a supplier wire datasheet
status: ground
note: The Sullins table row is labelled 250 °C, but the range printed in the same cell is 20 to 300 °C, so the range is recorded as printed.
source: sullins-ca510
where: Thermal Properties table, row CTE linear
- benchmark: specific_heat
label: Specific heat capacity, phosphor bronze C51000 wire
value: 0.38
unit: J/(g·°C)
scope: material
conditions:
form: wire
temperature: not stated
unit_in_source: 0.0908 BTU/lb-°F
method: Value printed in a supplier wire datasheet
status: ground
source: sullins-ca510
where: Thermal Properties table, row Specific Heat Capacity
- benchmark: elastic_modulus
label: Modulus of elasticity, phosphor bronze C51000 wire
value: 110
unit: GPa
scope: material
conditions:
form: wire
temperature: not stated
unit_in_source: 16000 ksi
method: Value printed in a supplier wire datasheet
status: ground
source: sullins-ca510
where: Mechanical Properties table, row Modulus of Elasticity
- benchmark: electrical_resistivity
label: Electrical resistivity at 20 °C, phosphor bronze C51000 wire
value: 0.0000087
unit: ohm·cm
scope: material
conditions:
form: wire
temperature: 20 °C
unit_in_source: 8.7e-006 ohm-cm
method: Value printed in a supplier wire datasheet
status: ground
source: sullins-ca510
where: Electrical Properties table (page 2), row Electrical Resistivity
- benchmark: ultimate_tensile_strength
label: Tensile strength, H04 hard temper, minimum
value: 485
bound: lower
unit: MPa
scope: material
conditions:
temper: H04 hard
size: 1/4 to 1/2 inch round and hexagonal
unit_in_source: 70 ksi
standard: ASTM B139
method: Minimum value printed in a mechanical properties table of a supplier page
status: ground
source: concast-c51000
where: Mechanical properties table, H04 hard, row 1/4 to 1/2 inch round and hexagonal, column Tensile MPa
- benchmark: elongation
label: Elongation, H04 hard temper, minimum
value: 13
bound: lower
unit: '%'
scope: material
conditions:
temper: H04 hard
size: 1/4 to 1/2 inch round and hexagonal
basis: 4 times diameter or specimen thickness
method: Minimum value printed in a mechanical properties table of a supplier page
status: ground
source: concast-c51000
where: Mechanical properties table, H04 hard, row 1/4 to 1/2 inch round and hexagonal, column Elongation
- benchmark: ultimate_tensile_strength
label: Tensile strength, H08 spring temper, minimum
value: 790
bound: lower
unit: MPa
scope: material
conditions:
temper: H08 spring
size: 0.026 inch to 1/16 inch round
unit_in_source: 115 ksi
standard: ASTM B139
method: Minimum value printed in a mechanical properties table of a supplier page
status: ground
source: concast-c51000
where: Mechanical properties table, H08 spring, row 0.026 inch to 1/16 inch round inclusive, column Tensile MPa
- benchmark: ultimate_tensile_strength
label: Tensile strength, H02 wire
value: 585
unit: MPa
scope: material
conditions:
temper: H02
form: wire, 2 mm diameter
unit_in_source: 84800 psi
elongation_gauge: 50 mm
method: Value printed in a supplier wire datasheet
status: ground
source: sullins-ca510
where: Mechanical Properties table, row Tensile Strength Ultimate
- benchmark: yield_strength
label: Yield strength at 0.5 % extension, H02 wire
value: 550
unit: MPa
scope: material
conditions:
temper: H02
form: wire, 2 mm diameter
measure: 0.5 % extension under load
unit_in_source: 79800 psi
method: Value printed in a supplier wire datasheet
status: ground
source: sullins-ca510
where: Mechanical Properties table, row Tensile Strength Yield
- benchmark: elongation
label: Elongation at break, H02 wire
value: 8
unit: '%'
scope: material
conditions:
temper: H02
form: wire, 2 mm diameter
gauge_length: 50 mm
method: Value printed in a supplier wire datasheet
status: ground
source: sullins-ca510
where: Mechanical Properties table, row Elongation at Break
- benchmark: ultimate_tensile_strength
label: Ultimate tensile strength, hard temper sheet (France et al. 1969 data)
value: 607
unit: MPa
scope: material
conditions:
temper: hard, made by three roll and anneal cycles then a final roll to 0.040 inch
form: sheet
unit_in_source: 88 ksi
method: Value in the data file of a University of Waterloo materials page, which cites W.D. France et al., ASTM Journal of Materials, 1969; the source notes the data were digitised from plots and may contain errors
status: ground
source: fde-510-hard
where: Data file, row Su (ultimate tensile strength)
- benchmark: elongation
label: Elongation, hard temper sheet (France et al. 1969 data)
value: 9
unit: '%'
scope: material
conditions:
temper: hard
form: sheet
gauge_length: 2 inch
method: Value in the data file of a University of Waterloo materials page; digitised from plots
status: ground
source: fde-510-hard
where: Data file, row Elongation
corrosion:
- environment: Air and general service, rated qualitatively
headline: The wire datasheet rates corrosion resistance as good to excellent, with no numeric rate.
effect: The Sullins material notes say the alloy has good to excellent corrosion resistance. No corrosion rate in mm/year or mpy was printed on any page read in this run.
rating: low
conditions:
basis: qualitative statement from a wire datasheet
exposure: not stated
source: sullins-ca510
where: Material Notes
- environment: Alloy chemistry, tin content
headline: Tin is the element that gives phosphor bronze its corrosion resistance.
effect: Wikipedia says tin raises the corrosion resistance and strength of phosphor bronze, and that phosphorus raises wear resistance and stiffness. The article gives no corrosion data.
rating: low
conditions:
basis: general description, no test data
source: wikipedia-phosphor-bronze
where: Lead section, first paragraph
risks:
hazards:
- text: The Fisk Alloy SDS covers C51000, C51900 and C52100 as one product group. The solid alloy is Not Classified under GHS-US, with No Labeling Applicable. Cutting, welding, melting or grinding produce dust and fume that may cause irritation and metal fume fever, and fine dust in air may present an explosion hazard.
ghs: []
source: fisk-sds
where: Section 2, Hazard(s) identification (classification table and HNOC paragraphs)
- text: The same SDS says tin dust and fume may cause stannosis after chronic exposure, that tin has been shown to increase sarcoma incidence in animal tests, and that long-term phosphorus exposure may affect the kidney and liver.
ghs: []
source: fisk-sds
where: Section 11, Toxicological information, tin and phosphorus paragraphs
failure_risks:
- mode: Fatigue under reversed bending
trigger: Cyclic bending of hard temper sheet at stress amplitudes of about 170 to 340 MPa
consequence: In the digitised data, the sample with a stress amplitude of 337 MPa failed at 618,640 reversals, and the runout samples at 174 to 182 MPa survived 200,000,000 reversals without failure.
severity: moderate
source: fde-510-hard
where: Fatigue strain-life table, rows 1 and 22 to 24
- mode: Loss of the set temper on annealing
trigger: Heating into the annealing range of 475 to 675 °C
consequence: The temper is reset, so the H02, H04 or H08 strength values stop applying to the part.
severity: moderate
source: sullins-ca510
where: Processing Properties table, row Annealing Temperature
side_effects: []
handling:
- text: Specify the temper, since H04 hard, H08 spring and H02 wire have very different strengths, from 485 MPa minimum for H04 to 790 MPa minimum for H08 in fine round sizes.
source: concast-c51000
where: Mechanical properties tables, H04 hard and H08 spring
- text: Keep parts out of the annealing range of 475 to 675 °C unless the temper is to be reset.
source: sullins-ca510
where: Processing Properties table
- text: Control dust, fume and sparks when cutting, grinding or welding, since the SDS warns of irritation and a combustible dust hazard.
source: fisk-sds
where: Section 2, Hazard(s) identification
mitigations: []
uses:
- application: electronics-and-chips
device: Electrical contacts and wire forms
example: Sullins sells phosphor bronze 5 % Sn wire in the H02 temper as a contact material. Wikipedia says phosphor bronze wire is suited to springs, electrical contacts and wire forms where beryllium copper is not required.
source: wikipedia-phosphor-bronze
where: Industrial uses, electrical contacts paragraph; Sullins title block
- application: mechanisms
device: Springs, bushings and bearings
example: Wikipedia lists springs, bolts, bushings and bearings among phosphor bronze applications. The H08 spring temper is rated for spring use by its 790 MPa minimum tensile strength.
source: wikipedia-phosphor-bronze
where: Industrial uses section
- application: structures
device: Fasteners
example: Concast lists fasteners among the typical uses of C51000, and sells the alloy as bar, rod and wire in the H04 and H08 tempers.
source: concast-c51000
where: Typical uses section, fasteners
supply:
- subject: Copper (93.6 to 95.6 % of the alloy)
producers:
- country: Chile
share_percent: 23
year: 2025
- country: Congo (Kinshasa)
share_percent: 13.9
year: 2025
- country: Peru
share_percent: 11.7
year: 2025
- country: China
share_percent: 7.8
year: 2025
- country: Russia
share_percent: 5.7
year: 2025
critical_lists:
- list: U.S. Final 2025 List of Critical Minerals (copper added, 90 FR 50494)
listed: true
substitutes:
- 'USGS: aluminum substitutes for copper in electrical equipment and power cable, and optical fiber substitutes for copper in telecommunications applications.'
source: usgs-mcs2026-copper
where: World Mine and Refinery Production and Reserves table, mine production 2025e in thousand tons of copper content (world total 23,000; Chile 5,300; Congo (Kinshasa) 3,200; Peru 2,700; China 1,800; Russia 1,300); shares calculated from those values; Critical minerals text; Substitutes
- subject: Tin (4.20 to 5.80 % of the alloy)
producers:
- country: China
share_percent: 24.5
year: 2025
- country: Indonesia
share_percent: 21
year: 2025
- country: Peru
share_percent: 11.4
year: 2025
- country: Brazil
share_percent: 9.7
year: 2025
- country: Congo (Kinshasa)
share_percent: 9.3
year: 2025
critical_lists: []
recycling: 'USGS: about 17,000 tons of tin from old and new scrap was recycled in 2025, of which about 10,000 tons came from old scrap, and the scrap supplied 22 % of apparent consumption.'
substitutes:
- 'USGS: aluminum, glass, paper, plastic or tin-free steel substitute for tin in cans and containers; epoxy resins substitute for tin in solder.'
source: usgs-mcs2026-tin
where: 'World Mine Production and Reserves table, mine production 2025e in metric tons of tin content (world total 290,000; China 71,000; Indonesia 61,000; Peru 33,000; Brazil 28,000; Congo (Kinshasa) 27,000); shares calculated from those values; Recycling; Substitutes; Import Sources (2021-24): refined tin from Peru 31 %, Bolivia 27 %, Indonesia 15 %, Brazil 10 %'
documents:
- title: Concast, C51000 phosphor bronze product page (composition, physical, mechanical and designation tables)
type: datasheet
url: https://concast.com/c51000.php
- title: aircraftmaterials.com, Phosphor Bronze CDA 510 (UNS C51000)
type: datasheet
url: https://aircraftmaterials.com/data/copper/cda510.html
- title: Sullins Corporation, Contact Material Phosphor Bronze CA5100 H02 Temper Wire datasheet
type: datasheet
url: https://www.sullinscorp.com/wp-content/uploads/2016/07/Contact-Material-Phosphor-Bronze-CA5100-H02-Temper-Wire1.pdf
- title: University of Waterloo FDE data file, Phosphor Bronze C51000 hard temper (after W.D. France et al., ASTM Journal of Materials, 1969)
type: database
url: https://fde.uwaterloo.ca/Fde/Materials/Other/France/france-PhosphorBronze510-hard.html
- title: 'Wikipedia: Phosphor bronze'
type: database
url: https://en.wikipedia.org/wiki/Phosphor_bronze
- title: Fisk Alloy Safety Data Sheet FAWSDS-5, C51000, C51900, C52100 (revision 11-09-2017)
type: sds
url: https://fiskalloy.com/wp-content/uploads/2023/11/Fisk-Alloy-Safety-Datasheet-FAWSDS-5.pdf
year: 2017
- title: 'USGS Mineral Commodity Summaries 2026: Copper'
type: report
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-copper.pdf
year: 2026
- title: 'USGS Mineral Commodity Summaries 2026: Tin'
type: report
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-tin.pdf
year: 2026
gaps:
- No seawater or marine corrosion rate for C51000 was read. The Copper Development Association seawater guideline returned HTTP 401 and was not reachable; search snippets were not used as values.
- No W.Nr. number (2.1020) was confirmed. The search summary gave it from memory and it was not printed on any fetched page, so it is not entered.
- The EN numeric designation CW451K is printed on the Concast page; a Ningbo Jintian datasheet seen in search lists CW450K instead. The Concast value is used and the conflict is not resolved here.
- 'Two melting ranges conflict: Concast prints solidus 954 °C and liquidus 1049 °C; the Sullins datasheet prints solidus 975 °C and liquidus 1060 °C. Both are in the sources.'
- The Concast thermal conductivity is printed only in US units (40 Btu/sq ft/ft hr/°F at 68 °F) and is not converted. The Sullins value of 84 W/(m·K) is used.
- The France et al. 1969 data file prints an elastic modulus of 110300 with no unit. It is not entered, because the unit was not printed.
- Hardness (Rockwell B, typical 87 for H04) and machinability rating (20) are printed on the Concast and aircraftmaterials pages but not entered, because their names are not in the canonical property list.
- Outgassing, cold welding and atomic oxygen erosion for C51000 were not searched and no values are recorded.
- The USGS tin summary read in this run does not mention a critical minerals list, so the critical list field for tin is empty; the 2025 list was not checked separately.
- The Fisk SDS composition (copper 89 to 96 %, tin 4.2 to 9.0 %) covers three grades as one product group and is not used as the C51000 composition.
- Fatigue data are digitised from plots and are taken from one 1969 source; the values are not confirmed against the original paper.
- Atomic weights for the alloy elements were not read in this run, so the recipe parts carry weight shares only.
- The 545 MPa yield strength of the 1969 hard temper sheet is printed in the raw page (Sy line, 545 mpa), but verify-values could not match it, so the property was removed rather than kept unverified; the 607 MPa tensile and 9 % elongation from the same page are kept.
sources:
concast-c51000:
title: Concast, C51000 phosphor bronze product page
url: https://concast.com/c51000.php
kind: datasheet
license: Manufacturer product page (cited, not reproduced)
aircraftmaterials-cda510:
title: Phosphor Bronze CDA 510 (UNS C51000), aircraftmaterials.com
url: https://aircraftmaterials.com/data/copper/cda510.html
kind: datasheet
license: Web page (cited, not reproduced)
sullins-ca510:
title: Sullins Corporation, Contact Material Phosphor Bronze CA5100 H02 Temper Wire datasheet
url: https://www.sullinscorp.com/wp-content/uploads/2016/07/Contact-Material-Phosphor-Bronze-CA5100-H02-Temper-Wire1.pdf
kind: datasheet
license: Manufacturer datasheet (cited, not reproduced)
fde-510-hard:
title: University of Waterloo FDE, Phosphor Bronze C51000 hard temper, from W.D. France et al., ASTM Journal of Materials, 1969
url: https://fde.uwaterloo.ca/Fde/Materials/Other/France/france-PhosphorBronze510-hard.html
kind: database
license: University web page (cited, not reproduced)
wikipedia-phosphor-bronze:
title: 'Wikipedia: Phosphor bronze'
url: https://en.wikipedia.org/wiki/Phosphor_bronze
kind: web
license: CC BY-SA 4.0 (cited, not reproduced)
fisk-sds:
title: Fisk Alloy Safety Data Sheet FAWSDS-5, C51000, C51900, C52100
url: https://fiskalloy.com/wp-content/uploads/2023/11/Fisk-Alloy-Safety-Datasheet-FAWSDS-5.pdf
year: 2017
kind: datasheet
license: Manufacturer safety data sheet (cited, not reproduced)
usgs-mcs2026-copper:
title: Mineral Commodity Summaries 2026, Copper
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-copper.pdf
year: 2026
kind: report
license: public domain (USGS)
usgs-mcs2026-tin:
title: Mineral Commodity Summaries 2026, Tin
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-tin.pdf
year: 2026
kind: report
license: public domain (USGS)
license: CC-BY-4.0
updated: '2026-10-25'
review:
status: draft
method: assistant
checked_values: 16
unreachable: 3
caveats: 6
note: 'Values were read by an AI assistant on 2026-10-25 from the pages and PDFs named in each entry; the USGS PDFs were extracted with pdftotext. Unreachable: the Copper Development Association seawater guideline (HTTP 401), the Wieland B05 datasheet (HTTP 404) and the MakeItFrom page (HTTP 403). Caveats: the FDE values are digitised from plots; the melting ranges conflict between Concast and Sullins; the Concast and Sullins strengths are for different tempers and forms; the tin critical-list status was not read; the W.Nr. number was not confirmed.'
story:
risk_groups:
- title: For people
lead: The opened sources give a hazard for dust and fume from the alloy, not for the solid metal.
level: 1
verdict: Dust and fume, not solid metal
points:
- label: Solid alloy
line: The Fisk SDS classifies the solid alloy as Not Classified under GHS-US, with no labelling. Hazards come from the dust, fume and powder made when it is cut, ground or welded.
- label: Tin and phosphorus in dust
line: The same SDS says tin dust and fume can cause stannosis after chronic exposure and that tin has been shown to increase sarcoma incidence in animal tests. It also says long-term phosphorus exposure may affect the kidney and liver.
- title: If it fails
lead: The failure routes in the sources are fatigue in hard temper sheet and loss of temper on annealing.
points:
- label: Fatigue
line: In the digitised 1969 data, hard temper sheet failed at 618,640 reversals at 337 MPa stress amplitude, and samples at 174 to 182 MPa reached runout at 200,000,000 reversals.
- label: Annealing
line: The Sullins datasheet gives an annealing range of 475 to 675 °C. Heating into it resets the temper.
- title: Handling and storage
points:
- label: Specify the temper
line: H04 hard has 485 MPa minimum tensile strength, H08 spring has 790 MPa minimum in fine round sizes, and H02 wire has 550 MPa yield. Choose the temper before the strength is quoted.
- label: Dust
line: Control dust, fume and sparks when cutting, grinding or welding.
why: Phosphor bronze C51000 is a copper alloy with about 5 % tin and 0.2 % phosphorus. Tin gives it corrosion resistance and strength, and phosphorus adds wear resistance and stiffness. The Concast C51000 page gives a minimum tensile strength of 485 MPa for H04 hard bar and 790 MPa for H08 spring in fine round sizes. The Sullins H02 wire datasheet gives 585 MPa tensile and 550 MPa yield at 0.5 % extension. The alloy is used for springs, electrical contacts and fasteners.
uses:
- where: Electrical contacts
line: Sullins sells the H02 wire as a contact material, and Wikipedia says phosphor bronze wire is suited to springs, electrical contacts and wire forms where beryllium copper is not required.
- where: Springs and bushings
line: Wikipedia lists springs, bolts, bushings and bearings among phosphor bronze applications. The H08 spring temper has a minimum tensile strength of 790 MPa in fine round sizes.
- where: Fasteners
line: Concast lists fasteners among the typical uses of C51000 and sells it as bar, rod and wire.
can_do:
- label: Carry springs
value: 790 MPa minimum
benchmark: ultimate_tensile_strength
line: The H08 spring temper has a minimum tensile strength of 790 MPa for 0.026 inch to 1/16 inch round wire.
- label: Take the density
value: 8.86 g/cm3
benchmark: density
line: The Sullins datasheet gives a density of 8.86 g/cm3 at 20 °C.
- label: Conduct electricity
value: 15 %IACS
benchmark: electrical_conductivity
line: The Concast page gives an electrical conductivity of 15 %IACS at 68 °F, for an alloy with 5 % tin and 0.2 % phosphorus.
- label: Melt
value: 954 to 1049 °C
benchmark: melting_point
line: The solidus is 954 °C and the liquidus is 1049 °C in the Concast table. The Sullins sheet gives a different range.
compare: Compared with pure copper, the phosphor bronze C51000 gives much higher strength in the spring temper, and the datasheets give 15 %IACS electrical conductivity for the alloy. Compare the three rows below as examples; the copper profile uses a different grade.
compare_rows:
- label: Density
benchmark: density
- label: Electrical conductivity
benchmark: electrical_conductivity
- label: Thermal expansion
benchmark: cte
handling:
- Specify the temper, since the strength depends strongly on it.
- Keep parts out of the annealing range of 475 to 675 °C unless the temper is to be reset.
- Control dust, fume and sparks when cutting, grinding or welding.
good_for:
- 'Springs and electrical contacts: H08 spring temper gives 790 MPa minimum tensile strength in fine round sizes.'
- 'Solderable and brazeable parts: the Concast fabrication table rates soldering and brazing as excellent.'
- 'Fasteners and bushings: wear resistance is raised by phosphorus, according to Wikipedia.'
watch_out:
- Dust and fume when cut, ground or welded, per the Fisk SDS.
- Strength falls if the part is annealed above 475 °C.
- No seawater corrosion rate for C51000 was found in this run.
- Melting ranges differ between the Concast and Sullins sources.
verdict: Phosphor bronze C51000 is a tin-bronze with 4.20 to 5.80 % tin and 0.03 to 0.35 % phosphorus. Its strength depends strongly on temper, and the H08 spring temper gives 790 MPa minimum tensile strength in fine round sizes. The alloy is solderable and brazeable, and dust from machining is the main hazard. This profile lacks a seawater corrosion rate and the W.Nr. number.
recipe:
line: 'C51000 is a copper-tin-phosphorus alloy: copper is the matrix, and tin gives most of the strength and corrosion resistance. Phosphorus is a trace addition that Wikipedia says raises wear resistance and stiffness. Lead, zinc and iron are impurity limits, and the wrought bar, rod, wire and sheet are made by cold working and annealing.'
parts:
- name: Copper
symbol: Cu
share: 93.6 to 95.6 %
role: The matrix. The Sullins datasheet gives Cu 93.6 to 95.6 %; the Concast page gives copper as the remainder.
- name: Tin
symbol: Sn
share: 4.20 to 5.80 %
role: Gives most of the strength and corrosion resistance (Wikipedia, Concast composition table).
- name: Phosphorus
symbol: P
share: 0.03 to 0.35 %
role: A trace addition that raises wear resistance and stiffness (Wikipedia).
- name: Lead
symbol: Pb
share: 0.05 % max
role: Impurity limit.
- name: Zinc
symbol: Zn
share: 0.30 % max
role: Impurity limit.
- name: Iron
symbol: Fe
share: 0.10 % max
role: Impurity limit.
References
Every number above carries a reference number. Click one to see the source and where in it the value comes from.
| # | Source | Type | Year | Used for |
|---|---|---|---|---|
| Concast, C51000 phosphor bronze product page | datasheet | 8 values | ||
| Phosphor Bronze CDA 510 (UNS C51000), aircraftmaterials.com | datasheet | 0 values | ||
| Sullins Corporation, Contact Material Phosphor Bronze CA5100 H02 Temper Wire datasheet | datasheet | 12 values | ||
| University of Waterloo FDE, Phosphor Bronze C51000 hard temper, from W.D. France et al., ASTM Journal of Materials, 1969 | database | 3 values | ||
| Wikipedia: Phosphor bronze | web | 3 values | ||
| Fisk Alloy Safety Data Sheet FAWSDS-5, C51000, C51900, C52100 | datasheet | 2017 | 3 values | |
| Mineral Commodity Summaries 2026, Copper | report | 2026 | 1 value | |
| Mineral Commodity Summaries 2026, Tin | report | 2026 | 1 value |