Copper Alloy C50500
UNS C50500 · ASTM B103
C50500 is a low-tin phosphor bronze to ASTM B103, combining good cold-working behaviour with 48 % IACS electrical conductivity.
Reference datasheet — C50500 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the H04 condition
C50500 tempers and conditions
C50500 is supplied in 8 conditions, soft to hard. H04 is the default FabDigit quotes; the values on this page are for it.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Soft annealed | Choose for deep drawing, severe forming or when maximum ductility and conductivity are needed. | 97 | 276 | 48 | 60 HB | 50 % IACS |
Quarter hard | Choose when moderate forming is still required but annealed strength is insufficient. | 240 | 310 | 25 | 80 HB | 48 % IACS |
Half hard | General-purpose stamping temper balancing bend formability and spring strength. | 290 | 345 | 12 | 95 HB | 48 % IACS |
Half hard, stress-relieved | Choose when improved bend performance and stress-relaxation resistance are needed at half-hard strength. | 310 | 360 | 14 | 100 HB | 50 % IACS |
H04Default Full hard | Most commonly stocked strip temper for connectors, contacts and light springs. | 345 | 380 | 6 | 110 HB | 48 % IACS |
Extra hard | Choose for flat springs and contacts needing higher yield with minimal forming. | 380 | 415 | 4 | 125 HB | 47 % IACS |
Spring hard | Spring temper for flat springs, washers and contact fingers with good relaxation resistance. | 415 | 450 | 3 | 135 HB | 47 % IACS |
Extra spring hard | Maximum cold-worked strength for flat spring stock; almost no bendability across grain. | 435 | 470 | 3 | 140 HB | 47 % IACS |
What is C50500?
C50500 is a low-tin phosphor bronze to ASTM B103, combining good cold-working behaviour with 48 % IACS electrical conductivity. Default properties are 380 MPa tensile, 345 MPa yield, 6 % elongation and 110 HB (68 HRB), and tempers on file run O60, H01-H10 and HR02 in strip, sheet and wire. It is used where moderate strength has to coexist with current-carrying capacity, for example connectors and shielding. Machinability is poor at about 20 % of free-cutting brass, resistance welding is difficult because of the conductivity, and higher-tin C50700 or C51000 is the choice for heavier spring loads. C50500 has a density of 8.89 g/cm³ (0.321 lb/in³), heavier than 72% of copper alloy grades. It melts at 1,035°C (1,895 °F). C50500 has a yield strength of 345 MPa (50 ksi) and a tensile strength of 380 MPa (55.1 ksi) — stronger than 73% of copper alloy grades. Elongation at break is 6% and the elastic modulus is 117 GPa (17 Msi).
What is C50500 used for?
- electrical connectors
- springs
- washers
- cable shielding
Advantages
- Conducts heat well — 208 W/m·K (120.2 BTU/hr·ft·°F), better than 79% of copper alloy grades
- High electrical conductivity — 48 % IACS, better than 78% of copper alloy grades
Limitations
- Limited service temperature — 175°C (347 °F), worse than 92% of copper alloy grades
- Limited ductility — 6%, worse than 89% of copper alloy grades
- Difficult to machine — 25/100, worse than 86% of copper alloy grades
C50500 properties
Typical room-temperature values for C50500-H04; bars are the position among copper alloy grades.
Physical3
C50500 has a density of 8.89 g/cm³ (0.321 lb/in³), heavier than 72% of copper alloy grades. It melts at 1,035°C (1,895 °F).
Mechanical12
C50500 has a yield strength of 345 MPa (50 ksi) and a tensile strength of 380 MPa (55.1 ksi) — stronger than 73% of copper alloy grades. Elongation at break is 6% and the elastic modulus is 117 GPa (17 Msi).
Thermal6
C50500 is rated for continuous service to 175°C (347 °F). It conducts heat at 208 W/m·K (120.2 BTU/hr·ft·°F), better than 79% of copper alloy grades. Thermal expansion is 17.8 µm/m·K (9.89 µin/in·°F).
Electrical3
C50500 conducts electricity at 48 % IACS, better than 78% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is good (65/100), better than 58% of copper alloy grades.
Sustainability4
Producing a kilogram of C50500 takes about 57 MJ of energy and emits 3.7 kg of CO₂ — less than 52% of copper alloy grades. Typical recycled content is 40%.
Manufacturability8
C50500's machinability is poor (25/100, worse than 86% of copper alloy grades); weldability good (55/100); formability good (60/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the copper alloy family
Yield strength against density for every copper alloy grade FabDigit runs. C50500 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with C50500
Is C50500 easy to machine?
Gummy and low rated (~20% of free-cutting brass); use sharp positive-rake tools, high speed, light feed and generous coolant, or specify a leaded grade for screw-machine work.
Can C50500 be welded?
GTAW/GMAW with phosphor-bronze filler is workable; resistance welding is poor due to high conductivity, and soldering/brazing is the preferred joining route.
Can C50500 be formed, bent or molded?
Excellent cold formability in O60/H01; H04 and harder tempers need generous bend radii and preferably bending with the grain, with interstage annealing near 480–650 °C.
C50500 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Sn | 1 – 1.7 | 1.3 |
| Pdeoxidizer, adds strength | 0.03 – 0.35 | 0.2 |
| Fe | ≤ 0.05 | |
| Pb | ≤ 0.05 | |
| Zn | ≤ 0.3 | |
| CuCu + Ag, remainder | ≥ 98.7 (balance) |
What surface finishes work on C50500?
Not anodizable; takes tin, nickel, silver and gold plating readily and polishes to a bright bronze finish — passivate or lacquer to limit tarnish.
Surface treatments FabDigit runs on copper alloy parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Equivalent designations
Standards and trade names that resolve to Copper Alloy C50500 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- B103
How much does C50500 cost?
C50500 is a high-cost copper alloy ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
C50500 — frequently asked
What is C50500 used for?
C50500 is typically used for electrical connectors, springs, washers and cable shielding. In short: highest-conductivity phosphor bronze; 48 % IACS spring alloy; good cold formability.
What is the yield strength of C50500?
C50500 has a typical yield strength of 345 MPa (50 ksi) and a tensile strength of 380 MPa (55.1 ksi) — stronger than 73% of copper alloy grades. Strength varies by condition: see the 8 listed tempers.
Is C50500 easy to machine?
Not especially — machinability is rated poor (25/100, worse than 86% of copper alloy grades). Gummy and low rated (~20% of free-cutting brass); use sharp positive-rake tools, high speed, light feed and generous coolant, or specify a leaded grade for screw-machine work.
Can C50500 be welded?
Yes — weldability is rated good (55/100). GTAW/GMAW with phosphor-bronze filler is workable; resistance welding is poor due to high conductivity, and soldering/brazing is the preferred joining route.
What surface finishes work on C50500?
Not anodizable; takes tin, nickel, silver and gold plating readily and polishes to a bright bronze finish — passivate or lacquer to limit tarnish.
Can C50500 be formed, bent or molded?
Excellent cold formability in O60/H01; H04 and harder tempers need generous bend radii and preferably bending with the grain, with interstage annealing near 480–650 °C.
What is the maximum service temperature of C50500?
C50500 is rated for continuous use to about 175°C (347 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between C50500-H04 and C50500-O60?
H04 is the default condition — most commonly stocked strip temper for connectors, contacts and light springs. O60: choose for deep drawing, severe forming or when maximum ductility and conductivity are needed. Yield strength is 345 MPa in H04 versus 97 MPa in O60.
How much does C50500 cost?
C50500 is a high-cost copper alloy ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- ASTM B103/B103M — Phosphor Bronze Plate, Sheet, Strip and Rolled Bar — ASTM International (2019)
- CDA Alloy Datasheet C50500 — Copper Development Association (2023)
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- GB/T 2059 / GB/T 2049 (QSn1.5-0.2) — SAC (2017)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.