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Copper Alloy C71900-TB00

Heat-treated state

UNS C71900

TB00 = solution heat treated

Pick for deep forming/stamping of complex parts that will be precipitation hardened after shaping.

High cost $$$$

Values for the TB00 condition

Other C71900 tempers and conditions

C71900 is listed in 8 conditions; see the grade overview at C71900.

Compare all 8 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
TB00This page
Solution heat treated
Pick for deep forming/stamping of complex parts that will be precipitation hardened after shaping.20048040130 HB4 % IACS
Solution heat treated and cold worked, quarter hard
Light cold work for parts needing moderate stiffness with residual bend formability before aging.40056020160 HB4 % IACS
Solution heat treated and cold worked, half hard
Mid-strength cold-rolled strip/rod for parts that will be aged to final spring properties.50062012190 HB4 % IACS
TF00Default
Solution heat treated and precipitation hardened
Standard supply condition: best balance of high strength, ductility and stress-relaxation resistance for springs and connectors.5507601524 HRC5.5 % IACS
Solution heat treated and cold worked, full hard
Fully cold-worked strip/wire where maximum as-rolled strength is needed prior to precipitation hardening.620700620 HRC4 % IACS
TD01 and precipitation hardened
Use where aged strength must rise above TF00 but some bend formability is still required.7208301027 HRC5.8 % IACS
TD02 and precipitation hardened
Common spring-strip condition for connector contacts needing high contact force with modest bending.830900630 HRC6 % IACS
TD04 and precipitation hardened
Maximum-strength condition for flat springs and preloaded contacts formed to generous bend radii only.930970333 HRC6 % IACS

What is C71900-TB00?

C71900-TB00 is C71900 heat treated to TB00 — pick for deep forming/stamping of complex parts that will be precipitation hardened after shaping. C71900-TB00 has a yield strength of 200 MPa (29 ksi) and a tensile strength of 480 MPa (69.6 ksi) — weaker than 54% of copper alloy grades. Elongation at break is 40% and the elastic modulus is 152 GPa (22 Msi). C71900-TB00 has a density of 8.94 g/cm³ (0.323 lb/in³), heavier than 90% of copper alloy grades. It melts at 1,200°C (2,192 °F). TF00 is the default condition FabDigit quotes; TB00 is available on request or by drawing note.

Advantages

  • Stiff — 152 GPa (22 Msi), better than 99% of copper alloy grades
  • Good corrosion resistance — 78/100, better than 94% of copper alloy grades
  • Ductile — tolerates forming and impact — 40%, better than 84% of copper alloy grades
  • Forms and bends easily — 75/100, better than 82% of copper alloy grades

Limitations

  • Poor heat conductor — 26 W/m·K (15 BTU/hr·ft·°F), worse than 98% of copper alloy grades
  • Low electrical conductivity — 4 % IACS, worse than 98% of copper alloy grades
  • Difficult to machine — 22/100, worse than 94% of copper alloy grades
  • High embodied carbon — 5.5 kg CO₂/kg, worse than 89% of copper alloy grades

C71900-TB00 properties

Typical room-temperature values for C71900-TB00; 11 are specific to this condition. Other listed values are C71900 reference data and may not represent this condition. Bars are the position among copper alloy grades.

Physical3

C71900-TB00 has a density of 8.94 g/cm³ (0.323 lb/in³), heavier than 90% of copper alloy grades. It melts at 1,200°C (2,192 °F).

Density8.94 g/cm³0.32 lb/in³
Melting Point (Solidus)1,200°C2,192 °F
Liquidus Temperature1,240°C2,264 °F

Mechanical14

C71900-TB00 has a yield strength of 200 MPa (29 ksi) and a tensile strength of 480 MPa (69.6 ksi) — weaker than 54% of copper alloy grades. Elongation at break is 40% and the elastic modulus is 152 GPa (22 Msi).

Elastic (Young's) Modulus152 GPa22 Msi
Shear Modulus57 GPa8.3 Msi
Bulk Modulus150 GPa21.8 Msi
Poisson's Ratio0.33
Tensile Strength (Ultimate)480 MPa69.6 ksi
Yield Strength (0.2% offset)200 MPa29 ksi
Elongation at Break40%
Reduction in Area35%
Shear Strength470 MPa68.2 ksi
Fatigue Strength (Endurance Limit)190 MPa27.6 ksi
Charpy V-Notch Impact (RT)60 J44.3 ft·lbf
Hardness, Brinell130 HB
Hardness, Rockwell C24 HRC
Hardness, Vickers250 HV

Thermal6

C71900-TB00 is rated for continuous service to 200°C (392 °F). It conducts heat at 26 W/m·K (15 BTU/hr·ft·°F), worse than 98% of copper alloy grades. Thermal expansion is 15.5 µm/m·K (8.61 µin/in·°F).

Thermal Conductivity26 W/m·K15 BTU/hr·ft·°F
Specific Heat Capacity377 J/kg·K0.09 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)15.5 µm/m·K8.6 µin/in·°F
Latent Heat of Fusion205 J/g88.1 BTU/lb
Max Service Temperature (continuous)200°C392 °F
Min Service Temperature-196°C-321 °F

Electrical3

C71900-TB00 conducts electricity at 4 % IACS, worse than 98% of copper alloy grades.

Electrical Conductivity4 % IACS
Electrical Resistivity3.13×10⁻⁷ Ω·m12.3 µΩ·in
Magnetic Responsenon-magnetic

Chemical & Environmental3

Corrosion resistance is very good (78/100), better than 94% of copper alloy grades.

Galvanic Potential (seawater, vs SCE)-0.25 V
Corrosion ResistanceVery good78/100
Chemical Resistance SummaryExcellent in seawater and brackish water with good resistance to biofouling, erosion-corrosion and chloride SCC; attacked by oxidizing acids, ammonia/amines and sulphide-polluted seawater.

Sustainability4

Producing a kilogram of C71900-TB00 takes about 75 MJ of energy and emits 5.5 kg of CO₂ — more than 88% of copper alloy grades. Typical recycled content is 25%.

Embodied Energy (primary production)75 MJ/kg32,244 BTU/lb
Embodied Carbon (primary production)5.5 kg CO₂/kg
Embodied Water320 L/kg38.3 gal/lb
Typical Recycled Content25%

Manufacturability7

C71900-TB00's machinability is poor (22/100, worse than 94% of copper alloy grades); weldability good (55/100); formability very good (75/100).

MachinabilityPoor22/100
Machinability Rating (AISI 1212 = 100 %)20%
WeldabilityGood55/100
Formability (cold)Very good75/100
Brazeability / SolderabilityVery good70/100
PolishabilityVery good80/100
Anodizing Responsen/a — copper alloy, not anodizable; use electroplating (Ni/Au) or passivation

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

Working with C71900-TB00

Is C71900 easy to machine?

Gummy, work-hardening Cu-Ni: use sharp positive-rake carbide, rigid setups, heavy constant feed and flood coolant; rate ~20% of free-cutting brass and lower again after aging.

Can C71900 be welded?

GTAW/GMAW with Cu-Ni (ERCuNi) or matching filler is possible, but the HAZ loses the aged condition — re-solution treat and re-age for full strength.

Can C71900 be formed, bent or molded?

Form, stamp and coin in the solution-treated TB00 condition, then precipitation harden; aged tempers need generous bend radii (≥2t transverse) to avoid cracking.

What surface finishes work on C71900?

Not anodizable; takes a bright mechanical or electropolish and accepts Ni/Au or Sn electroplating for connector contact surfaces.

C71900 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
Niincludes Co28 – 3330
Crprecipitation-hardening element2.2 – 32.6
Fe≤ 0.50.2
Mn0.2 – 10.5
Si≤ 0.150.05
Tigrain/precipitate control≤ 0.20.1
Zrgrain refiner≤ 0.20.12
Zn≤ 0.05—
Pb≤ 0.02—
C≤ 0.10.04
Curemainder, approx. 65–68%balance—

C71900-TB00 — frequently asked

What is C71900-TB00 used for?

C71900-TB00 is typically used for springs, electrical connectors, relay contacts and high-temperature fasteners. In short: strongest wrought cupronickel; age-hardening spring alloy; holds load to 320 °C.

What is the yield strength of C71900-TB00?

C71900-TB00 has a typical yield strength of 200 MPa (29 ksi) and a tensile strength of 480 MPa (69.6 ksi) — weaker than 54% of copper alloy grades. Strength varies by condition: see the 8 listed tempers.

Is C71900-TB00 easy to machine?

Not especially — machinability is rated poor (22/100, worse than 94% of copper alloy grades). Gummy, work-hardening Cu-Ni: use sharp positive-rake carbide, rigid setups, heavy constant feed and flood coolant; rate ~20% of free-cutting brass and lower again after aging.

Can C71900-TB00 be welded?

Yes — weldability is rated good (55/100). GTAW/GMAW with Cu-Ni (ERCuNi) or matching filler is possible, but the HAZ loses the aged condition — re-solution treat and re-age for full strength.

What surface finishes work on C71900-TB00?

Not anodizable; takes a bright mechanical or electropolish and accepts Ni/Au or Sn electroplating for connector contact surfaces.

Can C71900-TB00 be formed, bent or molded?

Form, stamp and coin in the solution-treated TB00 condition, then precipitation harden; aged tempers need generous bend radii (≥2t transverse) to avoid cracking.

What is the maximum service temperature of C71900-TB00?

C71900-TB00 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 C71900-TF00 and C71900-TH04?

TF00 is the default condition — standard supply condition: best balance of high strength, ductility and stress-relaxation resistance for springs and connectors. TH04: maximum-strength condition for flat springs and preloaded contacts formed to generous bend radii only. Yield strength is 550 MPa in TF00 versus 930 MPa in TH04.

Sources

  1. Copper Alloy C71900 alloy data (UNS listing) — Copper Development Association (2023)
  2. ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials — ASM International (1990)
  3. ASM Specialty Handbook: Copper and Copper Alloys — ASM International (2001)
  4. ASTM B846 — Standard Terminology for Copper and Copper Alloys (temper designations) — ASTM (2020)
  5. Copper-nickel alloys for seawater service — technical guidance — Nickel Institute / CDA UK (2020)

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.