Copper Alloy C15500
UNS C15500
C15500 is a silver-bearing copper in which a small silver addition raises the softening and annealing temperature without reducing conductivity, so cold-worked strength survives soldering and brazing heat.
Reference datasheet — C15500 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
C15500 tempers and conditions
C15500 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 |
|---|---|---|---|---|---|---|
Light annealed | Softest supply condition — pick it for deep drawing, severe bending or when maximum conductivity and formability matter. | 80 | 235 | 42 | 45 HB | 93 % IACS |
Quarter hard | Light temper for parts that still need moderate bending but more stiffness than soft strip. | 205 | 270 | 25 | 70 HB | 92 % IACS |
Half hard | Best all-round strip temper: usable bend radii with roughly double the annealed yield strength. | 270 | 310 | 14 | 88 HB | 92 % IACS |
H04Default Full hard | Standard stocked temper for lead frames, commutator segments and contacts that must survive solder/braze heat with strength retained. | 310 | 345 | 6 | 100 HB | 92 % IACS |
Spring hard | Choose for flat springs and press contacts where elastic limit matters more than bendability. | 345 | 380 | 4 | 108 HB | 91 % IACS |
Extra spring hard | Higher cold-work level for thin contact springs needing extra elastic deflection. | 365 | 400 | 3 | 112 HB | 91 % IACS |
Strain hardened, quarter hard | Very heavily rolled strip for high-force miniature springs; bends only with the grain and generous radii. | 380 | 415 | 2.5 | 116 HB | 91 % IACS |
Strain hardened, half hard | Maximum strength temper of the C15500 strip range — flat parts, minimal forming, highest spring rate. | 400 | 430 | 2 | 120 HB | 90 % IACS |
What is C15500?
C15500 is a silver-bearing copper in which a small silver addition raises the softening and annealing temperature without reducing conductivity, so cold-worked strength survives soldering and brazing heat. It is supplied as strip and bar in O50 and H01–H14 tempers for commutator and lead-frame work, with 92% IACS, 344 W/m·K, 310 MPa yield, 345 MPa tensile and service to 250 °C. Machinability is poor at 22 because the metal is gummy like pure copper; C14510 or C14520 are the free-machining alternatives when chip control matters. C15500 has a density of 8.94 g/cm³ (0.323 lb/in³), heavier than 90% of copper alloy grades. It melts at 1,065°C (1,949 °F). C15500 has a yield strength of 310 MPa (45 ksi) and a tensile strength of 345 MPa (50 ksi) — stronger than 64% of copper alloy grades. Elongation at break is 6% and the elastic modulus is 117 GPa (17 Msi).
What is C15500 used for?
- commutator bars
- motor windings
- lead frames requiring soldering resistance
Advantages
- High electrical conductivity — 92 % IACS, better than 89% of copper alloy grades
- Conducts heat well — 344 W/m·K (198.8 BTU/hr·ft·°F), better than 86% of copper alloy grades
Limitations
- Difficult to machine — 22/100, worse than 94% of copper alloy grades
- Limited ductility — 6%, worse than 89% of copper alloy grades
C15500 properties
Typical room-temperature values for C15500-H04; bars are the position among copper alloy grades.
Physical3
C15500 has a density of 8.94 g/cm³ (0.323 lb/in³), heavier than 90% of copper alloy grades. It melts at 1,065°C (1,949 °F).
Mechanical12
C15500 has a yield strength of 310 MPa (45 ksi) and a tensile strength of 345 MPa (50 ksi) — stronger than 64% of copper alloy grades. Elongation at break is 6% and the elastic modulus is 117 GPa (17 Msi).
Thermal6
C15500 is rated for continuous service to 250°C (482 °F). It conducts heat at 344 W/m·K (198.8 BTU/hr·ft·°F), better than 86% of copper alloy grades. Thermal expansion is 17.6 µm/m·K (9.78 µin/in·°F).
Electrical3
C15500 conducts electricity at 92 % IACS, better than 89% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is good (68/100), better than 69% of copper alloy grades.
Sustainability4
Producing a kilogram of C15500 takes about 55 MJ of energy and emits 3.6 kg of CO₂ — less than 72% of copper alloy grades. Typical recycled content is 30%.
Manufacturability8
C15500's machinability is poor (22/100, worse than 94% of copper alloy grades); weldability good (55/100); formability fair (45/100).
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. C15500 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with C15500
Is C15500 easy to machine?
Gummy like pure copper (≈20 % of AISI 1212); use sharp positive-rake tools, high speed, low feed and flood coolant, or specify H04+ temper to reduce built-up edge.
Can C15500 be welded?
Excellent for soldering and brazing; GTAW/resistance welding are workable but the very high thermal conductivity demands preheat and high heat input — welding destroys the cold-worked strength locally.
Can C15500 be formed, bent or molded?
Anneals softly and cold-works readily; O50/H01 for deep draws and tight bends, H04 and above only for gentle bends with the grain.
C15500 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 |
|---|---|---|
| Ag8–25 troy oz/ton silver addition; raises softening temperature | 0.03 – 0.1 | 0.06 |
| Pdeoxidiser | 0.04 – 0.08 | 0.06 |
| Mg | 0.08 – 0.13 | 0.1 |
| CuCu + Ag ≥ 99.75 % min | balance |
What surface finishes work on C15500?
Not anodisable; tin, silver or nickel plate for solderability and tarnish resistance, or apply benzotriazole/lacquer to keep bright copper.
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).
How much does C15500 cost?
C15500 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.
C15500 — frequently asked
What is C15500 used for?
C15500 is typically used for commutator bars, motor windings and lead frames requiring soldering resistance. In short: anneal-resistant high-conductivity copper; holds temper through soldering; 92% IACS, 250 °C service.
What is the yield strength of C15500?
C15500 has a typical yield strength of 310 MPa (45 ksi) and a tensile strength of 345 MPa (50 ksi) — stronger than 64% of copper alloy grades. Strength varies by condition: see the 8 listed tempers.
Is C15500 easy to machine?
Not especially — machinability is rated poor (22/100, worse than 94% of copper alloy grades). Gummy like pure copper (≈20 % of AISI 1212); use sharp positive-rake tools, high speed, low feed and flood coolant, or specify H04+ temper to reduce built-up edge.
Can C15500 be welded?
Yes — weldability is rated good (55/100). Excellent for soldering and brazing; GTAW/resistance welding are workable but the very high thermal conductivity demands preheat and high heat input — welding destroys the cold-worked strength locally.
What surface finishes work on C15500?
Not anodisable; tin, silver or nickel plate for solderability and tarnish resistance, or apply benzotriazole/lacquer to keep bright copper.
Can C15500 be formed, bent or molded?
Anneals softly and cold-works readily; O50/H01 for deep draws and tight bends, H04 and above only for gentle bends with the grain.
What is the maximum service temperature of C15500?
C15500 is rated for continuous use to about 250°C (482 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between C15500-H04 and C15500-O50?
H04 is the default condition — standard stocked temper for lead frames, commutator segments and contacts that must survive solder/braze heat with strength retained. O50: softest supply condition — pick it for deep drawing, severe bending or when maximum conductivity and formability matter. Yield strength is 310 MPa in H04 versus 80 MPa in O50.
How much does C15500 cost?
C15500 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 B747 / B152 (copper sheet, strip, plate and rolled bar) — ASTM International (2019)
- CDA UNS C15500 alloy datasheet (silver-bearing phosphorus-deoxidized copper) — Copper Development Association (2023)
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- ASM Handbook Vol.13B — Corrosion: Materials — ASM International (2005)
- GB/T 2059 / GB/T 2040 (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.