Copper Alloy C72700-TD01
Supply condition
UNS C72700
TD01 = solution heat treated and cold worked, quarter hard
Light cold work for formed parts that will be spinodal aged (to TH01) after stamping.
Values for the TD01 condition
Other C72700 tempers and conditions
C72700 is listed in 9 conditions; see the grade overview at C72700.
Compare all 9 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution heat treated | Softest, most formable condition; choose when deep forming or heavy coining precedes a customer spinodal age. | 240 | 480 | 35 | 72 HRB | 9 % IACS |
TD01This page Solution heat treated and cold worked, quarter hard | Light cold work for formed parts that will be spinodal aged (to TH01) after stamping. | 450 | 560 | 15 | 166 HB | 9 % IACS |
Solution heat treated and cold worked, half hard | Balanced strength/bendability strip for stamped springs that receive a post-form age. | 550 | 620 | 9 | 91 HRB | 9 % IACS |
Solution heat treated and cold worked, full hard | Hard cold-rolled strip for flat springs and contacts where only simple bends are needed before aging. | 680 | 720 | 4 | 96 HRB | 9 % IACS |
TH01Default TD01 and precipitation hardened | Most commonly stocked mill-hardened strip: high spring strength with usable bend formability and no post-form heat treatment. | 730 | 800 | 8 | 23 HRC | 11 % IACS |
Mill hardened, full hard | Producer-controlled mill-hardened temper balancing formability and yield strength for connector stamping lines. | 790 | 840 | 8 | 25 HRC | 11 % IACS |
TD02 and precipitation hardened | Higher-strength mill-hardened temper for compact contacts with moderate bend requirements. | 810 | 870 | 6 | 26 HRC | 11 % IACS |
TD04 and precipitation hardened | Maximum-strength aged strip for highly loaded flat springs where only gentle bends are formed. | 900 | 950 | 4 | 29 HRC | 11 % IACS |
Mill hardened, spring hard | Top mill-hardened strength level for miniature high-force contacts; formability is limited to gentle bends. | 950 | 1,000 | 4 | 30 HRC | 11 % IACS |
What is C72700-TD01?
C72700-TD01 is C72700 supplied in the TD01 condition — light cold work for formed parts that will be spinodal aged (to TH01) after stamping. C72700-TD01 has a yield strength of 450 MPa (65.3 ksi) and a tensile strength of 560 MPa (81.2 ksi) — stronger than 86% of copper alloy grades. Elongation at break is 15% and the elastic modulus is 125 GPa (18.1 Msi). C72700-TD01 has a density of 8.86 g/cm³ (0.32 lb/in³), heavier than 68% of copper alloy grades. It melts at 1,060°C (1,940 °F). TH01 is the default condition FabDigit quotes; TD01 is available on request or by drawing note.
Advantages
- High strength — 450 MPa (65.3 ksi), better than 86% of copper alloy grades
- Good corrosion resistance — 72/100, better than 84% of copper alloy grades
- Forms and bends easily — 65/100, better than 78% of copper alloy grades
Limitations
- Limited service temperature — 150°C (302 °F), worse than 96% of copper alloy grades
- Poor heat conductor — 28 W/m·K (16.2 BTU/hr·ft·°F), worse than 96% of copper alloy grades
- High embodied carbon — 4.8 kg CO₂/kg, worse than 84% of copper alloy grades
- Low electrical conductivity — 9 % IACS, worse than 78% of copper alloy grades
C72700-TD01 properties
Typical room-temperature values for C72700-TD01; 22 are specific to this condition. Other listed values are C72700 reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
C72700-TD01 has a density of 8.86 g/cm³ (0.32 lb/in³), heavier than 68% of copper alloy grades. It melts at 1,060°C (1,940 °F).
Mechanical12
C72700-TD01 has a yield strength of 450 MPa (65.3 ksi) and a tensile strength of 560 MPa (81.2 ksi) — stronger than 86% of copper alloy grades. Elongation at break is 15% and the elastic modulus is 125 GPa (18.1 Msi).
Thermal6
C72700-TD01 is rated for continuous service to 150°C (302 °F). It conducts heat at 28 W/m·K (16.2 BTU/hr·ft·°F), worse than 96% of copper alloy grades. Thermal expansion is 16.5 µm/m·K (9.17 µin/in·°F).
Electrical3
C72700-TD01 conducts electricity at 9 % IACS, worse than 78% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is very good (72/100), better than 84% of copper alloy grades.
Sustainability4
Producing a kilogram of C72700-TD01 takes about 68 MJ of energy and emits 4.8 kg of CO₂ — more than 83% of copper alloy grades. Typical recycled content is 25%.
Manufacturability7
C72700-TD01's machinability is poor (26/100, worse than 81% of copper alloy grades); weldability fair (35/100); formability good (65/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with C72700-TD01
Is C72700 easy to machine?
Machines like a tough Cu-Ni: ~20 % of free-cutting brass, use sharp carbide, positive rake, generous coolant and heavier feeds to avoid work hardening; aged tempers cut with better chip control than annealed.
Can C72700 be welded?
Resistance and laser welding are practical; fusion welding softens the aged spinodal structure in the HAZ, so join before aging or accept local strength loss — solders and silver brazes wet the alloy well.
Can C72700 be formed, bent or molded?
Form in TB00/TD01 for deep or tight bends then spinodal age (typically ~350–400 °C, several hours) for peak strength; mill-hardened TH/TM tempers allow only moderate bends, mostly good-way.
What surface finishes work on C72700?
Not anodizable — plate with Ni underlayer plus Sn, Ag or Au for contacts; takes a bright polish and forms a stable dull-bronze oxide in service.
C72700 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 | 8.5 – 9.5 | 9 |
| Sn | 5.5 – 6.5 | 6 |
| Mndeoxidizer/grain control | 0.05 – 0.3 | 0.15 |
| Mg | ≤ 0.15 | — |
| Nbmax, grain refiner | ≤ 0.1 | — |
| Fe | ≤ 0.5 | — |
| Zn | ≤ 0.5 | — |
| Pb | ≤ 0.02 | — |
| Curemainder, nominally ~84 % | balance | — |
C72700-TD01 — frequently asked
What is C72700-TD01 used for?
C72700-TD01 is typically used for high-reliability connectors, springs and electronic contacts. In short: spinodal-hardened Cu-Ni-Sn; stronger than C72500; beryllium-free contact alloy.
What is the yield strength of C72700-TD01?
C72700-TD01 has a typical yield strength of 450 MPa (65.3 ksi) and a tensile strength of 560 MPa (81.2 ksi) — stronger than 86% of copper alloy grades. Strength varies by condition: see the 9 listed tempers.
Is C72700-TD01 easy to machine?
Not especially — machinability is rated poor (26/100, worse than 81% of copper alloy grades). Machines like a tough Cu-Ni: ~20 % of free-cutting brass, use sharp carbide, positive rake, generous coolant and heavier feeds to avoid work hardening; aged tempers cut with better chip control than annealed.
Can C72700-TD01 be welded?
With care — weldability is rated fair (35/100). Resistance and laser welding are practical; fusion welding softens the aged spinodal structure in the HAZ, so join before aging or accept local strength loss — solders and silver brazes wet the alloy well.
What surface finishes work on C72700-TD01?
Not anodizable — plate with Ni underlayer plus Sn, Ag or Au for contacts; takes a bright polish and forms a stable dull-bronze oxide in service.
Can C72700-TD01 be formed, bent or molded?
Form in TB00/TD01 for deep or tight bends then spinodal age (typically ~350–400 °C, several hours) for peak strength; mill-hardened TH/TM tempers allow only moderate bends, mostly good-way.
What is the maximum service temperature of C72700-TD01?
C72700-TD01 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 C72700-TH01 and C72700-TB00?
TH01 is the default condition — most commonly stocked mill-hardened strip: high spring strength with usable bend formability and no post-form heat treatment. TB00: softest, most formable condition; choose when deep forming or heavy coining precedes a customer spinodal age. Yield strength is 730 MPa in TH01 versus 240 MPa in TB00.
Sources
- ASTM B740 — Copper-Nickel-Tin Spinodal Alloy Strip — ASTM International (2020)
- CDA Standard Designations for Wrought Copper Alloys (C72700) — Copper Development Association (2023)
- BrushForm 725 / Cu-9Ni-6Sn strip data — Materion (2022)
- ASM Handbook Vol. 2 — Properties of Copper and Copper 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.