Copper Alloy C75400
UNS C75400
C75400 is an intermediate-nickel wrought copper-nickel-zinc nickel silver in the C70000-C79999 family, hardened by cold rolling through OS070 to H08 tempers.
Reference datasheet — C75400 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
C75400 tempers and conditions
C75400 is supplied in 10 conditions, soft to hard. H02 is the default FabDigit quotes; the values on this page are for it.
Compare all 10 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed to 0.070 mm grain size | Softest commercial anneal — pick for deep drawing, spinning and severe bending of decorative parts. | 120 | 360 | 42 | 70 HB | — |
Annealed to 0.035 mm grain size | General-purpose anneal balancing formability with a fine surface after forming; common etching and stamping stock. | 145 | 380 | 40 | 78 HB | — |
Annealed to 0.025 mm grain size | Fine-grain anneal for moderate forming with smooth (orange-peel-free) polished and etched surfaces. | 165 | 395 | 37 | 85 HB | — |
Annealed to 0.015 mm grain size | Finest anneal — choose for shallow forming plus best etched detail and mirror polish on thin strip. | 190 | 415 | 32 | 95 HB | — |
1/8 hard | Slightly stiffened strip for parts needing flatness and moderate bending without full annealed softness. | 260 | 430 | 25 | 105 HB | — |
Quarter hard | Standard temper for etched nameplates and formed hardware needing some spring-back control. | 320 | 460 | 20 | 118 HB | — |
H02Default Half hard | Most stocked temper — good strength with enough ductility for 90° bends in quality hardware and trim. | 425 | 515 | 12 | 140 HB | — |
Full hard | Full-hard strip for flat springs, contacts and stiff formed sections with only gentle bends. | 510 | 585 | 5 | 165 HB | — |
Extra hard | Extra-hard temper for high-stiffness spring contacts and shear-cut flat parts; bending must follow the rolling-grain rule. | 570 | 640 | 3 | 185 HB | — |
Spring hard | Spring temper strip for flat springs and diaphragms where maximum elastic limit is needed; stress-relieve after forming. | 605 | 675 | 2 | 12 HRC | 6.3 % IACS |
What is C75400?
C75400 is an intermediate-nickel wrought copper-nickel-zinc nickel silver in the C70000-C79999 family, hardened by cold rolling through OS070 to H08 tempers. It balances the whiteness of the 65-18 grade against the formability of 65-10, with 425 MPa yield, 515 MPa tensile, 12% elongation and 140 HB (75 HRB) in the default condition, and is normally bought as strip and sheet for etching stock and hardware. Machinability is only about 20% of free-cutting brass and fusion welding is fair at best; service is limited to roughly 200 °C. Move to C75200 when maximum whiteness is required. C75400 has a density of 8.72 g/cm³ (0.315 lb/in³), lighter than 54% of copper alloy grades. It melts at 1,021°C (1,870 °F). C75400 has a yield strength of 425 MPa (61.6 ksi) and a tensile strength of 515 MPa (74.7 ksi) — stronger than 83% of copper alloy grades. Elongation at break is 12% and the elastic modulus is 125 GPa (18.1 Msi).
What is C75400 used for?
- etching plates
- hardware fittings
- musical instrument parts
- decorative trim
Advantages
- Polishes to a fine finish — 88/100, better than 97% of copper alloy grades
- High strength — 425 MPa (61.6 ksi), better than 83% of copper alloy grades
Limitations
- Low electrical conductivity — 6.5 % IACS, worse than 91% of copper alloy grades
- High embodied carbon — 5.2 kg CO₂/kg, worse than 88% of copper alloy grades
- Poor heat conductor — 37 W/m·K (21.4 BTU/hr·ft·°F), worse than 85% of copper alloy grades
C75400 properties
Typical room-temperature values for C75400-H02; bars are the position among copper alloy grades.
Physical3
C75400 has a density of 8.72 g/cm³ (0.315 lb/in³), lighter than 54% of copper alloy grades. It melts at 1,021°C (1,870 °F).
Mechanical12
C75400 has a yield strength of 425 MPa (61.6 ksi) and a tensile strength of 515 MPa (74.7 ksi) — stronger than 83% of copper alloy grades. Elongation at break is 12% and the elastic modulus is 125 GPa (18.1 Msi).
Thermal5
C75400 is rated for continuous service to 200°C (392 °F). It conducts heat at 37 W/m·K (21.4 BTU/hr·ft·°F), worse than 85% of copper alloy grades. Thermal expansion is 16.2 µm/m·K (9 µin/in·°F).
Electrical3
C75400 conducts electricity at 6.5 % IACS, worse than 91% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is good (66/100), better than 64% of copper alloy grades.
Sustainability4
Producing a kilogram of C75400 takes about 78 MJ of energy and emits 5.2 kg of CO₂ — more than 90% of copper alloy grades. Typical recycled content is 40%.
Manufacturability7
C75400's machinability is poor (30/100, worse than 67% of copper alloy grades); weldability fair (45/100); formability good (55/100).
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. C75400 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with C75400
Is C75400 easy to machine?
Gummy and abrasive — rating ~20 % of free-cutting brass; use sharp positive-rake carbide, high speed with light feeds and generous soluble-oil coolant.
Can C75400 be welded?
Solders and brazes readily and resistance-welds well; fusion welding is fair at best due to zinc fuming — prefer GTAW with matched Cu-Ni filler and good extraction.
Can C75400 be formed, bent or molded?
Excellent cold formability in OS tempers (deep draw, spin, coin); interanneal 600–750 °C between severe draws and stress-relieve cold-worked parts near 260 °C to avoid ammonia SCC.
C75400 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 |
|---|---|---|
| Cu | 63.5 – 66.5 | 65 |
| Niincludes Co | 14 – 16 | 15 |
| Mn | ≤ 0.5 | |
| Fe | ≤ 0.25 | |
| Pb | ≤ 0.1 | |
| Znremainder, nominally ~20 % | balance |
What surface finishes work on C75400?
Polishes to a bright silver-white finish; ideal for photochemical etching, bright/electroless nickel, silver or chrome plating, and clear lacquer for tarnish control (not anodizable).
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 C75400 cost?
C75400 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.
C75400 — frequently asked
What is C75400 used for?
C75400 is typically used for etching plates, hardware fittings, musical instrument parts and decorative trim. In short: balanced whiteness and formability; preferred etching stock; mid-nickel strip grade.
What is the yield strength of C75400?
C75400 has a typical yield strength of 425 MPa (61.6 ksi) and a tensile strength of 515 MPa (74.7 ksi) — stronger than 83% of copper alloy grades. Strength varies by condition: see the 10 listed tempers.
Is C75400 easy to machine?
Not especially — machinability is rated poor (30/100, worse than 67% of copper alloy grades). Gummy and abrasive — rating ~20 % of free-cutting brass; use sharp positive-rake carbide, high speed with light feeds and generous soluble-oil coolant.
Can C75400 be welded?
With care — weldability is rated fair (45/100). Solders and brazes readily and resistance-welds well; fusion welding is fair at best due to zinc fuming — prefer GTAW with matched Cu-Ni filler and good extraction.
What surface finishes work on C75400?
Polishes to a bright silver-white finish; ideal for photochemical etching, bright/electroless nickel, silver or chrome plating, and clear lacquer for tarnish control (not anodizable).
Can C75400 be formed, bent or molded?
Excellent cold formability in OS tempers (deep draw, spin, coin); interanneal 600–750 °C between severe draws and stress-relieve cold-worked parts near 260 °C to avoid ammonia SCC.
What is the maximum service temperature of C75400?
C75400 is rated for continuous use to about 200°C (392 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between C75400-H02 and C75400-OS070?
H02 is the default condition — most stocked temper — good strength with enough ductility for 90° bends in quality hardware and trim. OS070: softest commercial anneal — pick for deep drawing, spinning and severe bending of decorative parts. Yield strength is 425 MPa in H02 versus 120 MPa in OS070.
How much does C75400 cost?
C75400 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 B122/B122M — Copper-Nickel-Tin, Copper-Nickel-Zinc Plate, Sheet, Strip and Rolled Bar — ASTM International (2022)
- ASTM B151/B151M — Copper-Nickel-Zinc and Copper-Nickel Rod and Bar — ASTM International (2021)
- CDA Standard Designation & Properties Database, alloy C75400 — Copper Development Association (2023)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys (nickel silvers) — ASM International (1990)
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.