Copper Alloy C73100-H08
Supply condition
UNS C73100
H08 = spring hard
Pick for flat springs, clips and reed-type parts needing high elastic limit.
Values for the H08 condition
Other C73100 tempers and conditions
C73100 is listed in 7 conditions; see the grade overview at C73100.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Soft annealed | Pick for deep drawing, spinning and severe bending of decorative parts. | 125 | 340 | 43 | 60 HB | — |
Quarter hard | Pick when moderate forming is still needed but annealed strength is too low. | 275 | 400 | 25 | 100 HB | 10 % IACS |
H02Default Half hard | Most stocked general-purpose temper: balanced strength and bendability for trim, escutcheons and stamped hardware. | 345 | 450 | 15 | 65 HRB | — |
Full hard | Pick for flat blanked parts, light springs and stiff trim needing high strength with only gentle forming. | 450 | 525 | 5 | 78 HRB | — |
Extra hard | Pick for flat contacts, snap parts and stiff strip where formability is not required. | 520 | 585 | 3 | 84 HRB | — |
H08This page Spring hard | Pick for flat springs, clips and reed-type parts needing high elastic limit. | 560 | 620 | 2.5 | 190 HB | 9.5 % IACS |
Extra spring hard | Pick only for the highest-stiffness thin strip springs; essentially no bend formability. | 585 | 655 | 2 | 200 HB | 9.5 % IACS |
What is C73100-H08?
C73100-H08 is C73100 supplied in the H08 condition — pick for flat springs, clips and reed-type parts needing high elastic limit. C73100-H08 has a yield strength of 560 MPa (81.2 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 93% of copper alloy grades. Elongation at break is 2.5% and the elastic modulus is 125 GPa (18.1 Msi). C73100-H08 has a density of 8.73 g/cm³ (0.315 lb/in³), lighter than 53% of copper alloy grades. It melts at 1,040°C (1,904 °F). H02 is the default condition FabDigit quotes; H08 is available on request or by drawing note.
Advantages
- Polishes to a fine finish — 90/100, better than 99% of copper alloy grades
- High strength — 560 MPa (81.2 ksi), better than 93% of copper alloy grades
Limitations
- Limited ductility — 2.5%, worse than 97% of copper alloy grades
- Limited service temperature — 160°C (320 °F), worse than 92% of copper alloy grades
- High embodied carbon — 4.6 kg CO₂/kg, worse than 82% of copper alloy grades
- Poor heat conductor — 44 W/m·K (25.4 BTU/hr·ft·°F), worse than 78% of copper alloy grades
- Low electrical conductivity — 9.5 % IACS, worse than 76% of copper alloy grades
C73100-H08 properties
Typical room-temperature values for C73100-H08; 20 are specific to this condition. Other listed values are C73100 reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
C73100-H08 has a density of 8.73 g/cm³ (0.315 lb/in³), lighter than 53% of copper alloy grades. It melts at 1,040°C (1,904 °F).
Mechanical11
C73100-H08 has a yield strength of 560 MPa (81.2 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 93% of copper alloy grades. Elongation at break is 2.5% and the elastic modulus is 125 GPa (18.1 Msi).
Thermal6
C73100-H08 is rated for continuous service to 160°C (320 °F). It conducts heat at 44 W/m·K (25.4 BTU/hr·ft·°F), worse than 78% of copper alloy grades. Thermal expansion is 16.2 µm/m·K (9 µin/in·°F).
Electrical3
C73100-H08 conducts electricity at 9.5 % IACS, worse than 76% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is good (55/100), worse than 86% of copper alloy grades.
Sustainability4
Producing a kilogram of C73100-H08 takes about 65 MJ of energy and emits 4.6 kg of CO₂ — more than 81% of copper alloy grades. Typical recycled content is 35%.
Manufacturability8
C73100-H08's machinability is fair (40/100, better than 57% of copper alloy grades); weldability fair (45/100); formability poor (22/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with C73100-H08
Is C73100 easy to machine?
Gummy, low machinability (~20 % of free-cutting brass); use sharp positive-rake carbide tools, high speed, light feeds and generous coolant, or specify a leaded nickel silver for screw-machine work.
Can C73100 be welded?
Resistance and brazing/soldering are the preferred joining routes; fusion welding needs low heat input and risks zinc fume and porosity, and hot-short cracking in heavily cold-worked stock.
Can C73100 be formed, bent or molded?
Excellent cold formability in O60/H01 for deep drawing and spinning; stress-relieve after severe forming (about 260–300 °C) to avoid ammonia-related stress-corrosion cracking.
What surface finishes work on C73100?
Buffs to a bright silver-white finish; usually clear-lacquered, or nickel/chrome/silver plated for tarnish resistance — anodizing does not apply.
C73100 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 |
|---|---|---|
| Cuhigh-copper nickel silver base | 73.5 – 76.5 | 75 |
| NiNi + Co counted together | 8 – 10 | 9 |
| Fe | ≤ 0.25 | — |
| Mn | ≤ 0.5 | — |
| Pb | ≤ 0.1 | — |
| Zn | balance | — |
C73100-H08 — frequently asked
What is C73100-H08 used for?
C73100-H08 is typically used for decorative hardware, costume jewelry, zippers and musical instrument parts. In short: low-cost silver-look alloy; good deep-drawing nickel silver; low nickel content.
What is the yield strength of C73100-H08?
C73100-H08 has a typical yield strength of 560 MPa (81.2 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 93% of copper alloy grades. Strength varies by condition: see the 7 listed tempers.
Is C73100-H08 easy to machine?
Not especially — machinability is rated fair (40/100, better than 57% of copper alloy grades). Gummy, low machinability (~20 % of free-cutting brass); use sharp positive-rake carbide tools, high speed, light feeds and generous coolant, or specify a leaded nickel silver for screw-machine work.
Can C73100-H08 be welded?
With care — weldability is rated fair (45/100). Resistance and brazing/soldering are the preferred joining routes; fusion welding needs low heat input and risks zinc fume and porosity, and hot-short cracking in heavily cold-worked stock.
What surface finishes work on C73100-H08?
Buffs to a bright silver-white finish; usually clear-lacquered, or nickel/chrome/silver plated for tarnish resistance — anodizing does not apply.
Can C73100-H08 be formed, bent or molded?
Excellent cold formability in O60/H01 for deep drawing and spinning; stress-relieve after severe forming (about 260–300 °C) to avoid ammonia-related stress-corrosion cracking.
What is the maximum service temperature of C73100-H08?
C73100-H08 is rated for continuous use to about 160°C (320 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between C73100-H02 and C73100-H10?
H02 is the default condition — most stocked general-purpose temper: balanced strength and bendability for trim, escutcheons and stamped hardware. H10: pick only for the highest-stiffness thin strip springs; essentially no bend formability. Yield strength is 345 MPa in H02 versus 585 MPa in H10.
Sources
- Copper Alloy Datasheets (C7xxxx nickel silvers) — Copper Development Association (copper.org) (2023)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- ASTM B122/B122M — Copper-Nickel-Tin, Copper-Nickel-Zinc and Copper-Nickel Plate, Sheet, Strip and Rolled Bar — ASTM (2021)
- ASTM B36/B36M and temper designations per ASTM B601 — ASTM (2018)
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.