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Copper Alloy C76400-H02

Supply condition

UNS C76400

H02 = half hard

General-purpose strip temper for stamped parts needing strength plus light bending.

High cost $$$$

Values for the H02 condition

Other C76400 tempers and conditions

C76400 is listed in 7 conditions; see the grade overview at C76400.

Compare all 7 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
Annealed
Choose for deep drawing, spinning and severe forming before a final age/stress-relief or plating step.1703904090 HB—
Quarter hard
Choose when moderate strength must be combined with residual bending/forming ability.34045020120 HB—
H02This page
Half hard
General-purpose strip temper for stamped parts needing strength plus light bending.42551512145 HB—
H04Default
Full hard
The standard stock temper for flat springs, contacts and stamped structural strip where high yield strength is the priority.5105854165 HB—
Extra hard
Choose for flat springs and blanked parts with only very gentle forming after rolling.5706553180 HB—
Spring hard
Choose for springy contacts and clips loaded near the elastic limit; forming limited to large-radius bends with grain direction.6207052195 HB—
Extra spring hard
Maximum-strength strip/wire for flat springs and pretensioned contacts; essentially no formability across the grain.670750220 HRC5.5 % IACS

What is C76400-H02?

C76400-H02 is C76400 supplied in the H02 condition — general-purpose strip temper for stamped parts needing strength plus light bending. C76400-H02 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). C76400-H02 has a density of 8.7 g/cm³ (0.314 lb/in³), lighter than 56% of copper alloy grades. It melts at 1,040°C (1,904 °F). H04 is the default condition FabDigit quotes; H02 is available on request or by drawing note.

Advantages

  • Polishes to a fine finish — 85/100, better than 92% of copper alloy grades
  • High strength — 425 MPa (61.6 ksi), better than 83% of copper alloy grades

Limitations

  • Poor heat conductor — 29 W/m·K (16.8 BTU/hr·ft·°F), worse than 93% of copper alloy grades
  • Low electrical conductivity — 6 % IACS, worse than 93% of copper alloy grades
  • High embodied carbon — 5.5 kg CO₂/kg, worse than 89% of copper alloy grades

C76400-H02 properties

Typical room-temperature values for C76400-H02; 11 are specific to this condition. Other listed values are C76400 reference data and may not represent this condition. Bars are the position among copper alloy grades.

Physical3

C76400-H02 has a density of 8.7 g/cm³ (0.314 lb/in³), lighter than 56% of copper alloy grades. It melts at 1,040°C (1,904 °F).

Density8.7 g/cm³0.31 lb/in³
Melting Point (Solidus)1,040°C1,904 °F
Liquidus Temperature1,090°C1,994 °F

Mechanical12

C76400-H02 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).

Elastic (Young's) Modulus125 GPa18.1 Msi
Shear Modulus46 GPa6.7 Msi
Bulk Modulus130 GPa18.9 Msi
Poisson's Ratio0.35
Tensile Strength (Ultimate)515 MPa74.7 ksi
Yield Strength (0.2% offset)425 MPa61.6 ksi
Elongation at Break12%
Shear Strength350 MPa50.8 ksi
Fatigue Strength (Endurance Limit)190 MPa27.6 ksi
Hardness, Brinell145 HB
Hardness, Rockwell B80 HRB
Hardness, Vickers155 HV

Thermal5

C76400-H02 is rated for continuous service to 210°C (410 °F). It conducts heat at 29 W/m·K (16.8 BTU/hr·ft·°F), worse than 93% of copper alloy grades. Thermal expansion is 16.2 µm/m·K (9 µin/in·°F).

Thermal Conductivity29 W/m·K16.8 BTU/hr·ft·°F
Specific Heat Capacity377 J/kg·K0.09 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)16.2 µm/m·K9 µin/in·°F
Max Service Temperature (continuous)210°C410 °F
Min Service Temperature-196°C-321 °F

Electrical3

C76400-H02 conducts electricity at 6 % IACS, worse than 93% of copper alloy grades.

Electrical Conductivity6 % IACS
Electrical Resistivity2.9×10⁻⁷ Ω·m11.4 µΩ·in
Magnetic Responsenon-magnetic

Chemical & Environmental3

Corrosion resistance is good (68/100), better than 69% of copper alloy grades.

Galvanic Potential (seawater, vs SCE)-0.22 V
Corrosion ResistanceGood68/100
Chemical Resistance SummaryGood in fresh water, atmosphere, mild organics and foodstuffs; attacked by ammonia/amines (SCC risk in cold-worked tempers), oxidising acids, sulphides and strong chlorides.

Sustainability4

Producing a kilogram of C76400-H02 takes about 78 MJ of energy and emits 5.5 kg of CO₂ — more than 90% of copper alloy grades. Typical recycled content is 40%.

Embodied Energy (primary production)78 MJ/kg33,534 BTU/lb
Embodied Carbon (primary production)5.5 kg CO₂/kg
Embodied Water320 L/kg38.3 gal/lb
Typical Recycled Content40%

Manufacturability8

C76400-H02's machinability is poor (30/100, worse than 67% of copper alloy grades); weldability good (55/100); formability good (58/100).

MachinabilityPoor30/100
Machinability Rating (AISI 1212 = 100 %)25%
WeldabilityGood55/100
Formability (cold)Good58/100
CastabilityFair35/100
Brazeability / SolderabilityVery good80/100
PolishabilityExcellent85/100
Anodizing Responsen/a — copper alloy; use nickel/silver/chrome plating or clear lacquer instead

Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.

Working with C76400-H02

Is C76400 easy to machine?

Tough, gummy chips — use sharp positive-rake carbide, moderate speed with good coolant; free-machining leaded nickel silver (C79xxx) is preferable for screw-machine work.

Can C76400 be welded?

Best joined by resistance welding, silver brazing or soldering; fusion welding causes zinc fuming and porosity, so use low heat input and ventilation.

Can C76400 be formed, bent or molded?

Excellent deep-drawing and stamping in O61/H01; cold-worked tempers work-harden fast — interstage anneal near 600–750 °C and stress-relieve formed springs at ~250 °C.

What surface finishes work on C76400?

Takes a bright silver-white polish and readily accepts nickel, chrome, silver or gold plating; lacquer or plate for long-term tarnish resistance.

C76400 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.

ElementSpec limit (wt %)Nominal
Cuincludes Ag when reported58.5 – 61.560
NiNi + Co16.5 – 19.518
Pb≤ 0.05—
Fe≤ 0.25—
Mn≤ 0.5—
Znremainder, ≈22 %balance—

C76400-H02 — frequently asked

What is C76400-H02 used for?

C76400-H02 is typically used for electrical contacts, springs, hardware and musical instrument parts. In short: spring-temper nickel silver; highest hardness, low elongation; strip and wire grade.

What is the yield strength of C76400-H02?

C76400-H02 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 7 listed tempers.

Is C76400-H02 easy to machine?

Not especially — machinability is rated poor (30/100, worse than 67% of copper alloy grades). Tough, gummy chips — use sharp positive-rake carbide, moderate speed with good coolant; free-machining leaded nickel silver (C79xxx) is preferable for screw-machine work.

Can C76400-H02 be welded?

Yes — weldability is rated good (55/100). Best joined by resistance welding, silver brazing or soldering; fusion welding causes zinc fuming and porosity, so use low heat input and ventilation.

What surface finishes work on C76400-H02?

Takes a bright silver-white polish and readily accepts nickel, chrome, silver or gold plating; lacquer or plate for long-term tarnish resistance.

Can C76400-H02 be formed, bent or molded?

Excellent deep-drawing and stamping in O61/H01; cold-worked tempers work-harden fast — interstage anneal near 600–750 °C and stress-relieve formed springs at ~250 °C.

What is the maximum service temperature of C76400-H02?

C76400-H02 is rated for continuous use to about 210°C (410 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

What is the difference between C76400-H04 and C76400-O61?

H04 is the default condition — the standard stock temper for flat springs, contacts and stamped structural strip where high yield strength is the priority. O61: choose for deep drawing, spinning and severe forming before a final age/stress-relief or plating step. Yield strength is 510 MPa in H04 versus 170 MPa in O61.

Sources

  1. ASTM B122/B122M — Copper-Nickel-Zinc (Nickel Silver) Plate, Sheet, Strip and Rolled Bar — ASTM International (2022)
  2. ASTM B206/B206M — Copper-Nickel-Zinc (Nickel Silver) Wire — ASTM International (2019)
  3. CDA Alloy Datasheet C76400 (UNS composition, temper and physical property tables) — Copper Development Association (2023)
  4. 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.