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Copper Alloy C18400-TD02

Supply condition

UNS C18400

TD02 = solution heat treated and cold worked, half hard

Cold-drawn half-hard rod/wire for straightness and moderate strength where a customer ageing step is not planned.

High cost $$$$

Values for the TD02 condition

Other C18400 tempers and conditions

C18400 is listed in 7 conditions; see the grade overview at C18400.

Compare all 7 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
Annealed
Standard soft mill-annealed condition for bending, riveting and staking where high conductivity but only modest strength is needed.852304255 HB80 % IACS
Solution heat treated
Choose for maximum formability/deep forming before the customer performs the ageing (precipitation) treatment; conductivity is low until aged.952404060 HB42 % IACS
TD02This page
Solution heat treated and cold worked, half hard
Cold-drawn half-hard rod/wire for straightness and moderate strength where a customer ageing step is not planned.33038014110 HB75 % IACS
TF00Default
Solution heat treated and precipitation hardened
The standard stocked electrode/contact condition: ~80% IACS with roughly 470 MPa tensile — pick it for spot-welding electrodes and current-carrying structural parts.38047018140 HB82 % IACS
Solution heat treated and cold worked, full hard
Hard-drawn unaged wire/rod where springiness and dimensional straightness matter more than peak strength.39043010125 HB74 % IACS
TD01 and precipitation hardened
Cold work before ageing raises yield strength above TF00 while keeping ~80% IACS — used for contact arms, commutator segments and high-load electrode holders.45051515150 HB80 % IACS
TD04 and precipitation hardened
Highest-strength commercial condition for small rod, wire and strip where maximum yield strength with high conductivity is needed.48555012160 HB80 % IACS

What is C18400-TD02?

C18400-TD02 is C18400 supplied in the TD02 condition — cold-drawn half-hard rod/wire for straightness and moderate strength where a customer ageing step is not planned. C18400-TD02 has a yield strength of 330 MPa (47.9 ksi) and a tensile strength of 380 MPa (55.1 ksi) — stronger than 69% of copper alloy grades. Elongation at break is 14% and the elastic modulus is 115 GPa (16.7 Msi). C18400-TD02 has a density of 8.89 g/cm³ (0.321 lb/in³), heavier than 72% of copper alloy grades. It melts at 1,070°C (1,958 °F). TF00 is the default condition FabDigit quotes; TD02 is available on request or by drawing note.

Advantages

  • Conducts heat well — 300 W/m·K (173.3 BTU/hr·ft·°F), better than 83% of copper alloy grades
  • High electrical conductivity — 75 % IACS, better than 83% of copper alloy grades

C18400-TD02 properties

Typical room-temperature values for C18400-TD02; 12 are specific to this condition. Other listed values are C18400 reference data and may not represent this condition. Bars are the position among copper alloy grades.

Physical3

C18400-TD02 has a density of 8.89 g/cm³ (0.321 lb/in³), heavier than 72% of copper alloy grades. It melts at 1,070°C (1,958 °F).

Density8.89 g/cm³0.32 lb/in³
Melting Point (Solidus)1,070°C1,958 °F
Liquidus Temperature1,080°C1,976 °F

Mechanical12

C18400-TD02 has a yield strength of 330 MPa (47.9 ksi) and a tensile strength of 380 MPa (55.1 ksi) — stronger than 69% of copper alloy grades. Elongation at break is 14% and the elastic modulus is 115 GPa (16.7 Msi).

Elastic (Young's) Modulus115 GPa16.7 Msi
Shear Modulus44 GPa6.4 Msi
Bulk Modulus138 GPa20 Msi
Poisson's Ratio0.34
Tensile Strength (Ultimate)380 MPa55.1 ksi
Yield Strength (0.2% offset)330 MPa47.9 ksi
Elongation at Break14%
Reduction in Area55%
Shear Strength250 MPa36.3 ksi
Fatigue Strength (Endurance Limit)150 MPa21.8 ksi
Hardness, Brinell110 HB
Hardness, Rockwell B65 HRB

Thermal6

C18400-TD02 is rated for continuous service to 250°C (482 °F). It conducts heat at 300 W/m·K (173.3 BTU/hr·ft·°F), better than 83% of copper alloy grades. Thermal expansion is 17 µm/m·K (9.44 µin/in·°F).

Thermal Conductivity300 W/m·K173 BTU/hr·ft·°F
Specific Heat Capacity385 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)250°C482 °F
Min Service Temperature-200°C-328 °F

Electrical3

C18400-TD02 conducts electricity at 75 % IACS, better than 83% of copper alloy grades.

Electrical Conductivity75 % IACS
Electrical Resistivity2.3×10⁻⁸ Ω·m0.906 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)-0.28 V
Corrosion ResistanceGood68/100
Chemical Resistance SummaryGood in fresh/sea water, neutral salts and non-oxidizing acids; attacked by ammonia/amines, oxidizing acids (HNO3), sulfides and moist halogens; oxidizes progressively above ~250 °C in air.

Sustainability4

Producing a kilogram of C18400-TD02 takes about 57 MJ of energy and emits 3.8 kg of CO₂ — less than 52% of copper alloy grades. Typical recycled content is 30%.

Embodied Energy (primary production)57 MJ/kg24,506 BTU/lb
Embodied Carbon (primary production)3.8 kg CO₂/kg
Embodied Water250 L/kg30 gal/lb
Typical Recycled Content30%

Manufacturability8

C18400-TD02's machinability is fair (45/100, better than 64% of copper alloy grades); weldability fair (45/100); formability fair (50/100).

MachinabilityFair45/100
Machinability Rating (AISI 1212 = 100 %)60%
WeldabilityFair45/100
Formability (cold)Fair50/100
CastabilityGood55/100
Brazeability / SolderabilityVery good70/100
PolishabilityVery good70/100
Anodizing Responsen/a — copper alloy; use plating (Ni, Ag) or chemical passivation instead of anodizing

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

Working with C18400-TD02

Is C18400 easy to machine?

Machines like tough copper — gummy chips; use sharp positive-rake carbide, high speed, generous coolant; machine in the aged (TF00/TH01) temper for best finish.

Can C18400 be welded?

Excellent for resistance welding as an electrode material; GTAW/EBW possible with He shielding and low heat input but the HAZ over-ages and loses ~30–40% strength, so re-age after welding where possible.

Can C18400 be formed, bent or molded?

Form, deep-draw or head in the TB00/O61 soft tempers then solution treat (~980–1000 °C, water quench) and age (~450–500 °C, 2–4 h) for final properties.

What surface finishes work on C18400?

No anodizing; use bright dip/pickle to remove Cr-rich oxide, then nickel or silver plating for contacts, or leave bare — natural patina forms in service.

C18400 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
Crprecipitation-hardening element0.4 – 1.20.8
Fe≤ 0.15—
Si≤ 0.1—
Al≤ 0.1—
Zn≤ 0.1—
Pb≤ 0.05—
CuCu + named elements 99.5 % min (Ag counted as Cu)balance—

C18400-TD02 — frequently asked

What is C18400-TD02 used for?

C18400-TD02 is typically used for resistance welding electrodes, electrical contacts, electrode tips and caps, switchgear current-carrying parts, connector bodies and conductive fixture components. In short: 82 % IACS chromium copper; 400 °C electrode service; age-hardenable, 18 % elongation.

What is the yield strength of C18400-TD02?

C18400-TD02 has a typical yield strength of 330 MPa (47.9 ksi) and a tensile strength of 380 MPa (55.1 ksi) — stronger than 69% of copper alloy grades. Strength varies by condition: see the 7 listed tempers.

Is C18400-TD02 easy to machine?

Reasonably — machinability is rated fair (45/100, better than 64% of copper alloy grades). Machines like tough copper — gummy chips; use sharp positive-rake carbide, high speed, generous coolant; machine in the aged (TF00/TH01) temper for best finish.

Can C18400-TD02 be welded?

With care — weldability is rated fair (45/100). Excellent for resistance welding as an electrode material; GTAW/EBW possible with He shielding and low heat input but the HAZ over-ages and loses ~30–40% strength, so re-age after welding where possible.

What surface finishes work on C18400-TD02?

No anodizing; use bright dip/pickle to remove Cr-rich oxide, then nickel or silver plating for contacts, or leave bare — natural patina forms in service.

Can C18400-TD02 be formed, bent or molded?

Form, deep-draw or head in the TB00/O61 soft tempers then solution treat (~980–1000 °C, water quench) and age (~450–500 °C, 2–4 h) for final properties.

What is the maximum service temperature of C18400-TD02?

C18400-TD02 is rated for continuous use to about 250°C (482 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

What is the difference between C18400-TF00 and C18400-O61?

TF00 is the default condition — the standard stocked electrode/contact condition: ~80% IACS with roughly 470 MPa tensile — pick it for spot-welding electrodes and current-carrying structural parts. O61: standard soft mill-annealed condition for bending, riveting and staking where high conductivity but only modest strength is needed. Yield strength is 380 MPa in TF00 versus 85 MPa in O61.

Sources

  1. ASTM B224 — Classification of Coppers — ASTM International (2021)
  2. ASTM B133 / B187 — Copper rod, bar and shapes — ASTM International (2020)
  3. CDA Alloy Datasheet — Chromium Copper (C182xx/C184xx) — Copper Development Association (2023)
  4. ASM Handbook Vol.2 — Properties of Nonferrous Alloys — ASM International (1990)
  5. RWMA Class 2 electrode material bulletin — Resistance Welder Manufacturers' Association (2015)

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.