Copper Alloy C77600-O60
Temper
UNS C77600
O60 = soft annealed
Pick for deep drawing, spinning and severe forming of hardware and instrument parts.
Values for the O60 condition
Other C77600 tempers and conditions
C77600 is listed in 8 conditions; see the grade overview at C77600.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
O60This page Soft annealed | Pick for deep drawing, spinning and severe forming of hardware and instrument parts. | 170 | 400 | 40 | 90 HB | 5.8 % IACS |
Quarter hard | Pick when moderate bending or forming is still needed but annealed strength is too low. | 380 | 480 | 20 | 127 HB | 5.6 % IACS |
H02Default Half hard | Default stock condition — best balance of strength, bendability and surface finish for hardware and fittings. | 470 | 550 | 10 | 150 HB | 5.5 % IACS |
Drawn and stress-relieved | Pick for cold-worked parts that must resist stress-corrosion cracking in ammonia-bearing or humid service. | 480 | 560 | 10 | 155 HB | 5.5 % IACS |
Full hard | Pick for flat stamped parts, screws and fittings needing higher strength with only gentle bends. | 550 | 620 | 5 | 10 HRC | 5.4 % IACS |
Extra hard | Pick for flat springs and contacts where high strength matters more than formability. | 610 | 690 | 3 | 14 HRC | 5.3 % IACS |
Spring hard | Pick for spring washers, clips and elastic contact members made by simple forming. | 660 | 740 | 2 | 17 HRC | 5.3 % IACS |
Extra spring hard | Pick for the highest strength flat springs in thin strip; forming limited to very large bend radii. | 700 | 780 | 2 | 20 HRC | 5.2 % IACS |
What is C77600-O60?
C77600-O60 is C77600 in the O60 temper — pick for deep drawing, spinning and severe forming of hardware and instrument parts. C77600-O60 has a yield strength of 170 MPa (24.7 ksi) and a tensile strength of 400 MPa (58 ksi) — weaker than 62% of copper alloy grades. Elongation at break is 40% and the elastic modulus is 125 GPa (18.1 Msi). C77600-O60 has a density of 8.7 g/cm³ (0.314 lb/in³), lighter than 56% of copper alloy grades. It melts at 1,030°C (1,886 °F). H02 is the default condition FabDigit quotes; O60 is available on request or by drawing note.
Advantages
- Polishes to a fine finish — 88/100, better than 97% of copper alloy grades
- Forms and bends easily — 90/100, better than 89% of copper alloy grades
- Ductile — tolerates forming and impact — 40%, better than 84% of copper alloy grades
- Readily welded — 60/100, better than 76% of copper alloy grades
Limitations
- Low electrical conductivity — 5.8 % IACS, worse than 94% of copper alloy grades
- Difficult to machine — 22/100, worse than 94% of copper alloy grades
- Poor heat conductor — 31 W/m·K (17.9 BTU/hr·ft·°F), worse than 91% of copper alloy grades
- High embodied carbon — 4.5 kg CO₂/kg, worse than 79% of copper alloy grades
C77600-O60 properties
Typical room-temperature values for C77600-O60; 20 are specific to this condition. Other listed values are C77600 reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
C77600-O60 has a density of 8.7 g/cm³ (0.314 lb/in³), lighter than 56% of copper alloy grades. It melts at 1,030°C (1,886 °F).
Mechanical14
C77600-O60 has a yield strength of 170 MPa (24.7 ksi) and a tensile strength of 400 MPa (58 ksi) — weaker than 62% of copper alloy grades. Elongation at break is 40% and the elastic modulus is 125 GPa (18.1 Msi).
Thermal6
C77600-O60 is rated for continuous service to 250°C (482 °F). It conducts heat at 31 W/m·K (17.9 BTU/hr·ft·°F), worse than 91% of copper alloy grades. Thermal expansion is 16.2 µm/m·K (9 µin/in·°F).
Electrical3
C77600-O60 conducts electricity at 5.8 % IACS, worse than 94% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is good (68/100), better than 69% of copper alloy grades.
Sustainability4
Producing a kilogram of C77600-O60 takes about 62 MJ of energy and emits 4.5 kg of CO₂ — more than 76% of copper alloy grades. Typical recycled content is 40%.
Manufacturability7
C77600-O60's machinability is poor (22/100, worse than 94% of copper alloy grades); weldability good (60/100); formability excellent (90/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with C77600-O60
Is C77600 easy to machine?
Unleaded and gummy — use sharp positive-rake carbide, high speed, generous coolant and chip-breaking geometry; rating ≈20 % of free-cutting brass.
Can C77600 be welded?
Braze and soft-solder readily with silver filler; resistance welding is fair, fusion welding needs zinc-fume extraction and low heat input to avoid dezincification and porosity.
Can C77600 be formed, bent or molded?
Excellent deep-drawing and stamping in O60/H01; interstage anneal at 600–750 °C, and stress-relieve at 260–300 °C after heavy cold work to prevent SCC.
What surface finishes work on C77600?
Polishes to a bright silver-white finish; commonly buffed, lacquered, or nickel/chrome/silver plated — anodizing does not apply.
C77600 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 by convention | 55 – 58 | 56.5 |
| NiNi + Co | 12.5 – 15.5 | 14 |
| Mn | ≤ 0.5 | 0.15 |
| Fe | ≤ 0.25 | — |
| Pbunleaded grade | ≤ 0.05 | — |
| Zn | balance | — |
C77600-O60 — frequently asked
What is C77600-O60 used for?
C77600-O60 is typically used for musical instrument hardware, decorative fittings and electrical parts. In short: general-purpose nickel silver; bright silver-white surface; balanced strength and forming.
What is the yield strength of C77600-O60?
C77600-O60 has a typical yield strength of 170 MPa (24.7 ksi) and a tensile strength of 400 MPa (58 ksi) — weaker than 62% of copper alloy grades. Strength varies by condition: see the 8 listed tempers.
Is C77600-O60 easy to machine?
Not especially — machinability is rated poor (22/100, worse than 94% of copper alloy grades). Unleaded and gummy — use sharp positive-rake carbide, high speed, generous coolant and chip-breaking geometry; rating ≈20 % of free-cutting brass.
Can C77600-O60 be welded?
Yes — weldability is rated good (60/100). Braze and soft-solder readily with silver filler; resistance welding is fair, fusion welding needs zinc-fume extraction and low heat input to avoid dezincification and porosity.
What surface finishes work on C77600-O60?
Polishes to a bright silver-white finish; commonly buffed, lacquered, or nickel/chrome/silver plated — anodizing does not apply.
Can C77600-O60 be formed, bent or molded?
Excellent deep-drawing and stamping in O60/H01; interstage anneal at 600–750 °C, and stress-relieve at 260–300 °C after heavy cold work to prevent SCC.
What is the maximum service temperature of C77600-O60?
C77600-O60 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 C77600-H02 and C77600-O60?
H02 is the default condition — default stock condition — best balance of strength, bendability and surface finish for hardware and fittings. O60: pick for deep drawing, spinning and severe forming of hardware and instrument parts. Yield strength is 470 MPa in H02 versus 170 MPa in O60.
Sources
- CDA UNS Standard Designations for Wrought Copper Alloys — C77600 nickel silver — Copper Development Association (2023)
- ASTM B122/B122M — Copper-Nickel-Tin, Copper-Nickel-Zinc Plate, Sheet, Strip and Rolled Bar — ASTM International (2022)
- ASTM B151/B151M — Copper-Nickel-Zinc (Nickel Silver) and Copper-Nickel Rod and Bar — ASTM International (2019)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.