Copper Alloy C40500
UNS C40500
C40500 is a low-zinc, tin-bearing brass — informally called penny bronze — that pairs good cold formability with the corrosion resistance the tin addition provides.
Reference datasheet — C40500 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 H02 condition
C40500 tempers and conditions
C40500 is supplied in 9 conditions, soft to hard. H02 is the default FabDigit quotes; the values on this page are for it.
Compare all 9 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed to 0.035 mm grain size | Softest commercial strip temper — pick for deep drawing, severe coining and heavy forming. | 105 | 275 | 45 | 60 HB | 41 % IACS |
Annealed to 0.015 mm grain size | Fine-grain anneal for formed parts needing a smooth, orange-peel-free surface after drawing. | 125 | 305 | 42 | 72 HB | 41 % IACS |
Quarter hard | Light temper for parts still needing bending/forming but stiffer than annealed stock. | 275 | 330 | 28 | 100 HB | 40 % IACS |
H02Default Half hard | The general-purpose stocked strip temper — balanced strength and bendability for stampings and contacts. | 330 | 385 | 12 | 120 HB | 40 % IACS |
Three-quarter hard | Use where higher stiffness is needed and only gentle, large-radius bends are required. | 370 | 420 | 8 | 133 HB | 40 % IACS |
Full hard | Standard hard strip for flat stampings, washers and blanked coin-type parts with little forming. | 400 | 455 | 5 | 145 HB | 39 % IACS |
Extra hard | High-strength flat stock for flat springs and clips formed only across the rolling direction. | 450 | 505 | 3 | 158 HB | 39 % IACS |
Spring hard | Spring-tempered strip for contacts and leaf springs needing high elastic limit; watch SCC in ammonia. | 480 | 540 | 3 | 168 HB | 38 % IACS |
Extra spring hard | Maximum cold-rolled strength; for flat springs with essentially no forming after rolling. | 505 | 560 | 2 | 175 HB | 38 % IACS |
What is C40500?
C40500 is a low-zinc, tin-bearing brass — informally called penny bronze — that pairs good cold formability with the corrosion resistance the tin addition provides. In the default temper it gives 330 MPa yield, 385 MPa tensile, 12 % elongation, 120 HB, 40 % IACS and service to 190 °C, and is supplied as strip and coil in OS035, OS015 and H01–H10 for coining and progressive-die stamping. It is unleaded, so machinability is only about 20 % of free-cutting brass (score 22), fusion welding is fair at best, and cold-worked parts need stress relief against ammonia stress-corrosion cracking. For turning-intensive parts switch to C36000. C40500 has a density of 8.86 g/cm³ (0.32 lb/in³), heavier than 68% of copper alloy grades. It melts at 1,035°C (1,895 °F). C40500 has a yield strength of 330 MPa (47.9 ksi) and a tensile strength of 385 MPa (55.8 ksi) — stronger than 69% of copper alloy grades. Elongation at break is 12% and the elastic modulus is 117 GPa (17 Msi).
What is C40500 used for?
- coinage blanks
- electrical contacts
- small stampings
Advantages
- Forms and bends easily — 62/100, better than 77% of copper alloy grades
Limitations
- Difficult to machine — 22/100, worse than 94% of copper alloy grades
C40500 properties
Typical room-temperature values for C40500-H02; bars are the position among copper alloy grades.
Physical3
C40500 has a density of 8.86 g/cm³ (0.32 lb/in³), heavier than 68% of copper alloy grades. It melts at 1,035°C (1,895 °F).
Mechanical12
C40500 has a yield strength of 330 MPa (47.9 ksi) and a tensile strength of 385 MPa (55.8 ksi) — stronger than 69% of copper alloy grades. Elongation at break is 12% and the elastic modulus is 117 GPa (17 Msi).
Thermal6
C40500 is rated for continuous service to 190°C (374 °F). It conducts heat at 170 W/m·K (98.2 BTU/hr·ft·°F), better than 74% of copper alloy grades. Thermal expansion is 18.4 µm/m·K (10.2 µin/in·°F).
Electrical3
C40500 conducts electricity at 40 % IACS, better than 74% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is good (66/100), better than 64% of copper alloy grades.
Sustainability4
Producing a kilogram of C40500 takes about 57 MJ of energy and emits 3.6 kg of CO₂ — less than 52% of copper alloy grades. Typical recycled content is 40%.
Manufacturability8
C40500's machinability is poor (22/100, worse than 94% of copper alloy grades); weldability fair (40/100); formability good (62/100).
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. C40500 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with C40500
Is C40500 easy to machine?
Unleaded tin brass machines gummy with long chips — rating ~20 % of free-cutting brass; use sharp positive-rake tools, high speed and flood coolant, or switch to C36000 if turning-intensive.
Can C40500 be welded?
Solders and brazes readily and resistance-welds well; arc/gas fusion welding is only fair because of zinc fuming and porosity.
Can C40500 be formed, bent or molded?
Excellent cold formability in OS tempers (deep draw, coin, roll-form); interanneal near 450–600 °C and stress-relieve cold-worked parts around 200 °C to avoid ammonia stress-corrosion cracking.
C40500 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 |
|---|---|---|
| Cuincludes Ag | 94 – 96 | 95 |
| Sn | 0.7 – 1.3 | 1 |
| Pb | ≤ 0.05 | |
| Fe | ≤ 0.05 | |
| Zn | balance |
What surface finishes work on C40500?
Not anodizable — buff or barrel-polish to a bright bronze finish, then lacquer, patinate, or electroplate with Ni/Sn/Ag over a suitable strike.
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 C40500 cost?
C40500 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.
C40500 — frequently asked
What is C40500 used for?
C40500 is typically used for coinage blanks, electrical contacts and small stampings. In short: coinage-grade tin brass; excellent coining and drawing; machining rating only 22.
What is the yield strength of C40500?
C40500 has a typical yield strength of 330 MPa (47.9 ksi) and a tensile strength of 385 MPa (55.8 ksi) — stronger than 69% of copper alloy grades. Strength varies by condition: see the 9 listed tempers.
Is C40500 easy to machine?
Not especially — machinability is rated poor (22/100, worse than 94% of copper alloy grades). Unleaded tin brass machines gummy with long chips — rating ~20 % of free-cutting brass; use sharp positive-rake tools, high speed and flood coolant, or switch to C36000 if turning-intensive.
Can C40500 be welded?
With care — weldability is rated fair (40/100). Solders and brazes readily and resistance-welds well; arc/gas fusion welding is only fair because of zinc fuming and porosity.
What surface finishes work on C40500?
Not anodizable — buff or barrel-polish to a bright bronze finish, then lacquer, patinate, or electroplate with Ni/Sn/Ag over a suitable strike.
Can C40500 be formed, bent or molded?
Excellent cold formability in OS tempers (deep draw, coin, roll-form); interanneal near 450–600 °C and stress-relieve cold-worked parts around 200 °C to avoid ammonia stress-corrosion cracking.
What is the maximum service temperature of C40500?
C40500 is rated for continuous use to about 190°C (374 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between C40500-H02 and C40500-OS035?
H02 is the default condition — the general-purpose stocked strip temper — balanced strength and bendability for stampings and contacts. OS035: softest commercial strip temper — pick for deep drawing, severe coining and heavy forming. Yield strength is 330 MPa in H02 versus 105 MPa in OS035.
How much does C40500 cost?
C40500 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 B36/B36M — Brass Plate, Sheet, Strip and Rolled Bar — ASTM International (2018)
- CDA/copper.org Alloy Database — C40500 — Copper Development Association (2024)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- ASM Handbook Vol. 13B — Corrosion: Materials — ASM International (2005)
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.