Copper Alloy C72800-TB00
Heat-treated state
UNS C72800
TB00 = solution heat treated
Pick for deep drawing, severe forming or coining before a customer ageing treatment.
Values for the TB00 condition
Other C72800 tempers and conditions
C72800 is listed in 8 conditions; see the grade overview at C72800.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
TB00This page Solution heat treated | Pick for deep drawing, severe forming or coining before a customer ageing treatment. | 300 | 585 | 32 | 76 HRB | 7 % IACS |
Quarter hard | Pick when moderate forming is still required but higher as-supplied stiffness than soft strip is wanted. | 550 | 690 | 18 | 90 HRB | 7.5 % IACS |
Full hard | Pick for flat blanked parts or as the pre-temper feeding a TH04 ageing cycle. | 790 | 860 | 6 | 22 HRC | 7.5 % IACS |
TF00Default Solution heat treated and precipitation hardened | Default stocked condition: formed soft then aged ~350 °C for high strength with usable ductility and best isotropy. | 800 | 930 | 12 | 30 HRC | 8 % IACS |
Spring hard | Pick for un-aged spring strip needing maximum as-rolled strength with only bend-radius-limited forming. | 880 | 930 | 3 | 26 HRC | 7.5 % IACS |
TD01 and precipitation hardened | Pick when a formed contact needs high aged strength but must still tolerate moderate bends before ageing. | 930 | 1,000 | 9 | 32 HRC | 8.5 % IACS |
TD04 and precipitation hardened | Pick for maximum spring force retention in connector contacts and highly loaded flat springs. | 1,080 | 1,140 | 5 | 36 HRC | 8.5 % IACS |
Spring temper cold rolled then spinodally aged | Pick for the highest available strength level in thin strip where forming is limited to gentle bends. | 1,170 | 1,240 | 3 | 39 HRC | 8.5 % IACS |
What is C72800-TB00?
C72800-TB00 is C72800 heat treated to TB00 — pick for deep drawing, severe forming or coining before a customer ageing treatment. C72800-TB00 has a yield strength of 300 MPa (43.5 ksi) and a tensile strength of 585 MPa (84.8 ksi) — stronger than 61% of copper alloy grades. Elongation at break is 32% and the elastic modulus is 127 GPa (18.4 Msi). C72800-TB00 has a density of 8.86 g/cm³ (0.32 lb/in³), heavier than 68% of copper alloy grades. It melts at 1,030°C (1,886 °F). TF00 is the default condition FabDigit quotes; TB00 is available on request or by drawing note.
Advantages
- Polishes to a fine finish — 85/100, better than 92% of copper alloy grades
- Good corrosion resistance — 74/100, better than 88% of copper alloy grades
- Forms and bends easily — 80/100, better than 83% of copper alloy grades
- Ductile — tolerates forming and impact — 32%, better than 77% of copper alloy grades
Limitations
- Limited service temperature — 150°C (302 °F), worse than 96% of copper alloy grades
- Poor heat conductor — 30 W/m·K (17.3 BTU/hr·ft·°F), worse than 91% of copper alloy grades
- High embodied carbon — 5.2 kg CO₂/kg, worse than 88% of copper alloy grades
- Low electrical conductivity — 7 % IACS, worse than 86% of copper alloy grades
C72800-TB00 properties
Typical room-temperature values for C72800-TB00; 13 are specific to this condition. Other listed values are C72800 reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
C72800-TB00 has a density of 8.86 g/cm³ (0.32 lb/in³), heavier than 68% of copper alloy grades. It melts at 1,030°C (1,886 °F).
Mechanical14
C72800-TB00 has a yield strength of 300 MPa (43.5 ksi) and a tensile strength of 585 MPa (84.8 ksi) — stronger than 61% of copper alloy grades. Elongation at break is 32% and the elastic modulus is 127 GPa (18.4 Msi).
Thermal6
C72800-TB00 is rated for continuous service to 150°C (302 °F). It conducts heat at 30 W/m·K (17.3 BTU/hr·ft·°F), worse than 91% of copper alloy grades. Thermal expansion is 16.5 µm/m·K (9.17 µin/in·°F).
Electrical3
C72800-TB00 conducts electricity at 7 % IACS, worse than 86% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is very good (74/100), better than 88% of copper alloy grades.
Sustainability4
Producing a kilogram of C72800-TB00 takes about 72 MJ of energy and emits 5.2 kg of CO₂ — more than 86% of copper alloy grades. Typical recycled content is 20%.
Manufacturability8
C72800-TB00's machinability is fair (35/100, better than 51% of copper alloy grades); weldability fair (40/100); formability very good (80/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with C72800-TB00
Is C72800 easy to machine?
Gummy and work-hardening in the soft temper — machine in the aged condition with sharp carbide tools, positive rake, moderate speed and generous coolant; chips are stringy (≈20% of AISI 1212).
Can C72800 be welded?
GTAW/EBW feasible with matching or Cu-Ni filler, but the HAZ loses spinodal hardening and Sn segregation can cause hot cracking — re-solution + re-age after welding if strength matters.
Can C72800 be formed, bent or molded?
Do all deep drawing, bending and coining in TB00/H01 temper, then age (typically 340–370 °C, 2–4 h) to final strength; aged strip tolerates only large-radius bends.
What surface finishes work on C72800?
Not anodizable; takes bright polishing well and is readily electroplated with Ni/Sn/Ag/Au underplates for connector contacts.
C72800 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 |
|---|---|---|
| Ni | 9.5 – 10.5 | 10 |
| Sn | 7.5 – 8.5 | 8 |
| Mndeoxidiser / grain control | 0.05 – 0.3 | 0.15 |
| Nbgrain refiner (per CDA registration) | 0.1 – 0.5 | 0.25 |
| Fe | ≤ 0.5 | — |
| Zn | ≤ 0.5 | — |
| Pb | ≤ 0.02 | — |
| Cu | balance | — |
C72800-TB00 — frequently asked
What is C72800-TB00 used for?
C72800-TB00 is typically used for high-strength connectors, battery contacts and switch springs. In short: high-tin spinodal alloy; holds spring force at 200 °C; beryllium-free high strength.
What is the yield strength of C72800-TB00?
C72800-TB00 has a typical yield strength of 300 MPa (43.5 ksi) and a tensile strength of 585 MPa (84.8 ksi) — stronger than 61% of copper alloy grades. Strength varies by condition: see the 8 listed tempers.
Is C72800-TB00 easy to machine?
Not especially — machinability is rated fair (35/100, better than 51% of copper alloy grades). Gummy and work-hardening in the soft temper — machine in the aged condition with sharp carbide tools, positive rake, moderate speed and generous coolant; chips are stringy (≈20% of AISI 1212).
Can C72800-TB00 be welded?
With care — weldability is rated fair (40/100). GTAW/EBW feasible with matching or Cu-Ni filler, but the HAZ loses spinodal hardening and Sn segregation can cause hot cracking — re-solution + re-age after welding if strength matters.
What surface finishes work on C72800-TB00?
Not anodizable; takes bright polishing well and is readily electroplated with Ni/Sn/Ag/Au underplates for connector contacts.
Can C72800-TB00 be formed, bent or molded?
Do all deep drawing, bending and coining in TB00/H01 temper, then age (typically 340–370 °C, 2–4 h) to final strength; aged strip tolerates only large-radius bends.
What is the maximum service temperature of C72800-TB00?
C72800-TB00 is rated for continuous use to about 150°C (302 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between C72800-TF00 and C72800-TB00?
TF00 is the default condition — default stocked condition: formed soft then aged ~350 °C for high strength with usable ductility and best isotropy. TB00: pick for deep drawing, severe forming or coining before a customer ageing treatment. Yield strength is 800 MPa in TF00 versus 300 MPa in TB00.
Sources
- ASTM B740 — Copper-Nickel-Tin Spinodal Alloy Strip — ASTM International (2020)
- CDA Alloy Database — C72800 Cu-Ni-Sn — Copper Development Association (2023)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- Spinodal Cu-Ni-Sn strip and bar data (ToughMet/Marunaka-type products) — alloy producers (2022)
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.