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Copper Alloy C81540-TF00

Precip hard · default condition

UNS C81540 · ASTM B824

TF00 = solution heat treated and precipitation hardened

Standard supplied condition for electrode holders, welding arms and mold inserts — full strength plus 45–55% IACS.

High cost $$$$

Values for the TF00 condition

Other C81540 tempers and conditions

C81540 is listed in 5 conditions; see the grade overview at C81540.

Compare all 5 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
Solution heat treated
Soft, supersaturated interim condition — machine or straighten here, then age to TF00.1503303080 HB20 % IACS
As centrifugally cast
Raw foundry condition; strength and conductivity are both low until heat treated — rarely used in service.1703502290 HB28 % IACS
As plaster cast
Chill-cast blanks with finer structure than sand; still normally aged to TF00 before use.18538020100 HB30 % IACS
As continuous cast
Continuous-cast bar/tube stock for machined electrode holders; heat treat after rough machining.19039020105 HB32 % IACS
TF00DefaultThis page
Solution heat treated and precipitation hardened
Standard supplied condition for electrode holders, welding arms and mold inserts — full strength plus 45–55% IACS.48062011185 HB50 % IACS

What is C81540-TF00?

C81540-TF00 is C81540 in the TF00 condition — standard supplied condition for electrode holders, welding arms and mold inserts — full strength plus 45–55% IACS. C81540-TF00 has a yield strength of 480 MPa (69.6 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 88% of copper alloy grades. Elongation at break is 11% and the elastic modulus is 131 GPa (19 Msi). C81540-TF00 has a density of 8.61 g/cm³ (0.311 lb/in³), lighter than 58% of copper alloy grades. It melts at 1,030°C (1,886 °F).

Advantages

  • High service temperature — 450°C (842 °F), better than 98% of copper alloy grades
  • Stiff — 131 GPa (19 Msi), better than 91% of copper alloy grades
  • High strength — 480 MPa (69.6 ksi), better than 88% of copper alloy grades
  • High electrical conductivity — 50 % IACS, better than 79% of copper alloy grades
  • Conducts heat well — 200 W/m·K (115.6 BTU/hr·ft·°F), better than 78% of copper alloy grades

C81540-TF00 properties

Typical room-temperature values for C81540-TF00; 11 are specific to this condition. Other listed values are C81540 reference data and may not represent this condition. Bars are the position among copper alloy grades.

Physical3

C81540-TF00 has a density of 8.61 g/cm³ (0.311 lb/in³), lighter than 58% of copper alloy grades. It melts at 1,030°C (1,886 °F).

Density8.61 g/cm³0.31 lb/in³
Melting Point (Solidus)1,030°C1,886 °F
Liquidus Temperature1,075°C1,967 °F

Mechanical14

C81540-TF00 has a yield strength of 480 MPa (69.6 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 88% of copper alloy grades. Elongation at break is 11% and the elastic modulus is 131 GPa (19 Msi).

Elastic (Young's) Modulus131 GPa19 Msi
Shear Modulus49 GPa7.1 Msi
Bulk Modulus130 GPa18.9 Msi
Poisson's Ratio0.33
Tensile Strength (Ultimate)620 MPa89.9 ksi
Yield Strength (0.2% offset)480 MPa69.6 ksi
Elongation at Break11%
Compressive Strength500 MPa72.5 ksi
Shear Strength390 MPa56.6 ksi
Fatigue Strength (Endurance Limit)170 MPa24.7 ksi
Charpy V-Notch Impact (RT)20 J14.8 ft·lbf
Hardness, Brinell185 HB
Hardness, Rockwell B92 HRB
Hardness, Vickers195 HV

Thermal6

C81540-TF00 is rated for continuous service to 450°C (842 °F). It conducts heat at 200 W/m·K (115.6 BTU/hr·ft·°F), better than 78% of copper alloy grades. Thermal expansion is 17 µm/m·K (9.44 µin/in·°F).

Thermal Conductivity200 W/m·K116 BTU/hr·ft·°F
Specific Heat Capacity376 J/kg·K0.09 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)17 µm/m·K9.4 µin/in·°F
Latent Heat of Fusion205 J/g88.1 BTU/lb
Max Service Temperature (continuous)450°C842 °F
Min Service Temperature-200°C-328 °F

Electrical3

C81540-TF00 conducts electricity at 50 % IACS, better than 79% of copper alloy grades.

Electrical Conductivity50 % IACS
Electrical Resistivity3.45×10⁻⁸ Ω·m1.36 µΩ·in
Magnetic Responsenon-magnetic

Chemical & Environmental3

Corrosion resistance is good (60/100), worse than 68% of copper alloy grades.

Galvanic Potential (seawater, vs SCE)-0.25 V
Corrosion ResistanceGood60/100
Chemical Resistance SummaryGood in fresh/industrial water, steam and mild atmospheres; attacked by ammonia/amines, oxidizing acids, sulphides and mercury compounds; forms protective oxide but should not run in high-velocity seawater.

Sustainability4

Producing a kilogram of C81540-TF00 takes about 58 MJ of energy and emits 3.8 kg of CO₂ — more than 61% of copper alloy grades. Typical recycled content is 45%.

Embodied Energy (primary production)58 MJ/kg24,936 BTU/lb
Embodied Carbon (primary production)3.8 kg CO₂/kg
Embodied Water260 L/kg31.2 gal/lb
Typical Recycled Content45%

Manufacturability7

C81540-TF00's machinability is good (55/100, better than 71% of copper alloy grades); weldability fair (35/100); formability poor (25/100).

MachinabilityGood55/100
Machinability Rating (AISI 1212 = 100 %)40%
WeldabilityFair35/100
Formability (cold)Poor25/100
CastabilityGood65/100
Brazeability / SolderabilityGood60/100
PolishabilityVery good70/100

Common Calculations5

Specific Strength (UTS / density)calculated72 kN·m/kg
Specific Stiffness (E / density)calculated15.2 MN·m/kg
Modulus of Resiliencecalculated879 kJ/m³
Thermal Diffusivitycalculated61.8 mm²/s
Thermal Shock Resistance Indexcalculated56

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

Working with C81540-TF00

Is C81540 easy to machine?

Machines like a tough medium-hard bronze — sharp positive-rake carbide, high speed, moderate feed and flood coolant; rough in TB00/as-cast and finish after aging to hold size.

Can C81540 be welded?

GTAW/GMAW with matching or Cu-Si filler is possible but the heat-affected zone over-ages and loses hardness; re-solution-treat and age critical parts, and prefer brazing/mechanical joints for repairs.

Can C81540 be formed, bent or molded?

Supplied as sand, permanent-mold or continuous castings; feed heavily and keep melt low in Fe/S — cold forming is essentially limited to light straightening in the TB00 condition.

What surface finishes work on C81540?

Takes a good mechanical polish for mold surfaces and can be nickel- or chrome-plated for wear/release; no anodizing — leave a bare oxide or oil film for electrical contact faces.

C81540 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
Ni2 – 32.5
Si0.4 – 0.80.6
Cr0.1 – 0.60.35
Feimpurity limit≤ 0.15—
Alimpurity limit≤ 0.1—
Pbimpurity limit≤ 0.02—
CuCu incl. Ag; Cu + named elements 99.5 % min≥ 93.6 (balance)—

C81540-TF00 — frequently asked

What is C81540-TF00 used for?

C81540-TF00 is typically used for resistance welding wheels, continuous-casting mold segments and high-load electrical castings. In short: strongest cast high-copper; 620 MPa at 50 % IACS; welding-wheel casting alloy.

What is the yield strength of C81540-TF00?

C81540-TF00 has a typical yield strength of 480 MPa (69.6 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 88% of copper alloy grades. Strength varies by condition: see the 5 listed tempers.

Is C81540-TF00 easy to machine?

Reasonably — machinability is rated good (55/100, better than 71% of copper alloy grades). Machines like a tough medium-hard bronze — sharp positive-rake carbide, high speed, moderate feed and flood coolant; rough in TB00/as-cast and finish after aging to hold size.

Can C81540-TF00 be welded?

With care — weldability is rated fair (35/100). GTAW/GMAW with matching or Cu-Si filler is possible but the heat-affected zone over-ages and loses hardness; re-solution-treat and age critical parts, and prefer brazing/mechanical joints for repairs.

What surface finishes work on C81540-TF00?

Takes a good mechanical polish for mold surfaces and can be nickel- or chrome-plated for wear/release; no anodizing — leave a bare oxide or oil film for electrical contact faces.

Can C81540-TF00 be formed, bent or molded?

Supplied as sand, permanent-mold or continuous castings; feed heavily and keep melt low in Fe/S — cold forming is essentially limited to light straightening in the TB00 condition.

What is the maximum service temperature of C81540-TF00?

C81540-TF00 is rated for continuous use to about 450°C (842 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

What is the difference between C81540-TF00 and C81540-TB00?

TF00 is the default condition — standard supplied condition for electrode holders, welding arms and mold inserts — full strength plus 45–55% IACS. TB00: soft, supersaturated interim condition — machine or straighten here, then age to TF00. Yield strength is 480 MPa in TF00 versus 150 MPa in TB00.

Sources

  1. ASTM B824 — General Requirements for Copper Alloy Castings — ASTM International (2021)
  2. CDA Alloy Data Sheet C81540 — Copper Development Association (copper.org) (2023)
  3. ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
  4. RWMA Bulletin 16 — Resistance Welding Electrode Materials (Class 3) — AWS/RWMA (2015)
  5. High-conductivity Cu-Ni-Si-Cr casting/electrode alloy datasheets — various copper foundries (2023)

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.