Copper Alloy C18100-TH04
Precip hard · default condition
UNS C18100
TH04 = tD04 and precipitation hardened
The usual stocked bar/rod condition: peak strength and hardness with ~80% IACS conductivity.
Values for the TH04 condition
Other C18100 tempers and conditions
C18100 is listed in 7 conditions; see the grade overview at C18100.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Fully softened material for severe forming or as a machining stock before re-solution treating. | 95 | 250 | 42 | 58 HB | 88 % IACS |
Solution heat treated | Soft supersaturated condition for deep forming or machining before ageing; conductivity is temporarily low. | 105 | 260 | 40 | 60 HB | 42 % IACS |
Solution heat treated and cold worked, full hard | Cold-drawn stock supplied for customers who will age-harden after machining. | 340 | 400 | 14 | 120 HB | 45 % IACS |
Solution heat treated and precipitation hardened | Standard aged condition for large sections, forgings and electrode blanks where cold work is impractical. | 390 | 470 | 18 | 145 HB | 82 % IACS |
TD01 and precipitation hardened | Intermediate strength with retained ductility for parts needing some subsequent bending. | 420 | 495 | 16 | 152 HB | 81 % IACS |
TD02 and precipitation hardened | Half-hard aged strip/rod balancing strength and formability. | 455 | 520 | 14 | 158 HB | 80 % IACS |
TH04DefaultThis page TD04 and precipitation hardened | The usual stocked bar/rod condition: peak strength and hardness with ~80% IACS conductivity. | 490 | 550 | 13 | 165 HB | 80 % IACS |
What is C18100-TH04?
C18100-TH04 is C18100 in the TH04 condition — the usual stocked bar/rod condition: peak strength and hardness with ~80% IACS conductivity. C18100-TH04 has a yield strength of 490 MPa (71.1 ksi) and a tensile strength of 550 MPa (79.8 ksi) — stronger than 88% of copper alloy grades. Elongation at break is 13% and the elastic modulus is 130 GPa (18.9 Msi). C18100-TH04 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).
Advantages
- High service temperature — 450°C (842 °F), better than 98% of copper alloy grades
- Stiff — 130 GPa (18.9 Msi), better than 89% of copper alloy grades
- High strength — 490 MPa (71.1 ksi), better than 88% of copper alloy grades
- Conducts heat well — 320 W/m·K (184.9 BTU/hr·ft·°F), better than 84% of copper alloy grades
- High electrical conductivity — 80 % IACS, better than 84% of copper alloy grades
Limitations
- Needs corrosion protection — 48/100, worse than 96% of copper alloy grades
C18100-TH04 properties
Typical room-temperature values for C18100-TH04; 14 are specific to this condition. Other listed values are C18100 reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
C18100-TH04 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).
Mechanical14
C18100-TH04 has a yield strength of 490 MPa (71.1 ksi) and a tensile strength of 550 MPa (79.8 ksi) — stronger than 88% of copper alloy grades. Elongation at break is 13% and the elastic modulus is 130 GPa (18.9 Msi).
Thermal6
C18100-TH04 is rated for continuous service to 450°C (842 °F). It conducts heat at 320 W/m·K (184.9 BTU/hr·ft·°F), better than 84% of copper alloy grades. Thermal expansion is 17 µm/m·K (9.44 µin/in·°F).
Electrical3
C18100-TH04 conducts electricity at 80 % IACS, better than 84% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is fair (48/100), worse than 96% of copper alloy grades.
Sustainability4
Producing a kilogram of C18100-TH04 takes about 57 MJ of energy and emits 3.8 kg of CO₂ — less than 52% of copper alloy grades. Typical recycled content is 25%.
Manufacturability8
C18100-TH04's machinability is poor (30/100, worse than 67% of copper alloy grades); weldability fair (45/100); formability fair (40/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with C18100-TH04
Is C18100 easy to machine?
Machines like tough copper — gummy, needs sharp positive-rake carbide, high speed, generous coolant and chip breaking; aged (TH04/TF00) stock cuts far better than solution-treated.
Can C18100 be welded?
GTAW/EBW/laser possible with matching filler but the heat-affected zone over-ages and loses ~30–40 % strength; re-solution treat and re-age where possible, or use brazing at the lowest practical temperature.
Can C18100 be formed, bent or molded?
Form in TB00/O61 and age afterwards; aged tempers tolerate only gentle bends (min bend radius ≈ 2–3 t) because of low residual ductility.
What surface finishes work on C18100?
Not anodizable; electroplate Ni/Ag or Ni-flash + Au for contacts, or protect the natural copper surface with benzotriazole/lacquer; polishes to a bright copper finish.
C18100 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 |
|---|---|---|
| Crprincipal precipitation hardener | 0.4 – 1.5 | 0.8 |
| Zrraises softening resistance | 0.08 – 0.2 | 0.13 |
| Mgdeoxidiser / strengthener | 0.04 – 0.08 | 0.06 |
| CuCu + named elements ≥ 99.5 % | balance | — |
C18100-TH04 — frequently asked
What is C18100-TH04 used for?
C18100-TH04 is typically used for resistance welding electrodes, rotor bars, contact wire and electrode holders. In short: 80 % IACS at 490 MPa; 450 °C softening resistance; beryllium-free electrode copper.
What is the yield strength of C18100-TH04?
C18100-TH04 has a typical yield strength of 490 MPa (71.1 ksi) and a tensile strength of 550 MPa (79.8 ksi) — stronger than 88% of copper alloy grades. Strength varies by condition: see the 7 listed tempers.
Is C18100-TH04 easy to machine?
Not especially — machinability is rated poor (30/100, worse than 67% of copper alloy grades). Machines like tough copper — gummy, needs sharp positive-rake carbide, high speed, generous coolant and chip breaking; aged (TH04/TF00) stock cuts far better than solution-treated.
Can C18100-TH04 be welded?
With care — weldability is rated fair (45/100). GTAW/EBW/laser possible with matching filler but the heat-affected zone over-ages and loses ~30–40 % strength; re-solution treat and re-age where possible, or use brazing at the lowest practical temperature.
What surface finishes work on C18100-TH04?
Not anodizable; electroplate Ni/Ag or Ni-flash + Au for contacts, or protect the natural copper surface with benzotriazole/lacquer; polishes to a bright copper finish.
Can C18100-TH04 be formed, bent or molded?
Form in TB00/O61 and age afterwards; aged tempers tolerate only gentle bends (min bend radius ≈ 2–3 t) because of low residual ductility.
What is the maximum service temperature of C18100-TH04?
C18100-TH04 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 C18100-TH04 and C18100-O61?
TH04 is the default condition — the usual stocked bar/rod condition: peak strength and hardness with ~80% IACS conductivity. O61: fully softened material for severe forming or as a machining stock before re-solution treating. Yield strength is 490 MPa in TH04 versus 95 MPa in O61.
Sources
- ASTM B441 — Copper-Chromium-Zirconium (C18100) Rod, Bar and Shapes — ASTM International (2019)
- CDA/UNS Alloy Datasheet C18100 — Copper Development Association (copper.org) (2023)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- RWMA Bulletin 16 — Resistance Welding Electrode Materials, Class 3 — AWS/RWMA (2017)
- CuCrZr (C18150/C18100) high-conductivity alloy datasheet — Wieland / Ningbo Powerway (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.