Copper Alloy C10200-M20
Finish state
UNS C10200 · ASTM B170 · EN Cu-OF, CW008A · JIS C1020 · GB TU2
M20 = as hot rolled
Mill condition for thick plate, billet and heavy busbar that will be machined or annealed afterwards.
Values for the M20 condition
Other C10200 tempers and conditions
C10200 is listed in 14 conditions; see the grade overview at C10200.
Compare all 14 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
ODefault Annealed | Most stocked condition: maximum ductility and conductivity for deep drawing, bending, gaskets, vacuum parts and busbar forming. | 69 | 221 | 45 | 45 HB | 101 % IACS |
Hot rolled and annealed | Fully softened hot-rolled/hot-worked oxygen-free copper plate, bar and shapes with maximum ductility and ~101% IACS conductivity. | 69 | 221 | 45 | 45 HB | 101 % IACS |
M20This page As hot rolled | Mill condition for thick plate, billet and heavy busbar that will be machined or annealed afterwards. | 75 | 220 | 45 | 45 HB | 101 % IACS |
Annealed to 0.025 mm grain size | Fine-grain anneal for strip that must be formed and then keep a smooth (non-orange-peel) surface. | 90 | 235 | 40 | 50 HB | 101 % IACS |
Eighth hard | Slight stiffening over annealed while keeping near-full formability; common for busbar and lead frames that still need bending. | 170 | 250 | 30 | 60 HB | 100.5 % IACS |
Light drawn | Light-drawn OF tube: stiffer than annealed but still bendable, used for vacuum and cryogenic lines. | 195 | 255 | 25 | 70 HB | 100 % IACS |
Quarter hard | Balanced strength/bendability for stamped contacts and shielding that see moderate forming. | 205 | 262 | 25 | 70 HB | 100 % IACS |
Half hard | Standard semi-rigid temper for bar, rod and strip needing handling stiffness with 90° bendability. | 250 | 290 | 14 | 80 HB | 100 % IACS |
Three-quarter hard | Intermediate step to full hard when higher yield is needed but full-hard brittleness in bending is unacceptable. | 275 | 315 | 10 | 88 HB | 99.5 % IACS |
Hard drawn | Hard-drawn seamless tube and rod for pressure lines, waveguides and machined vacuum hardware. | 275 | 315 | 15 | 90 HB | 99 % IACS |
Full hard | Highest routinely stocked strength for flat springs, hard-drawn wire/rod and machined parts needing chip control. | 310 | 345 | 6 | 95 HB | 99 % IACS |
Extra hard | Thin strip/wire needing extra stiffness where forming is limited to gentle radii. | 340 | 365 | 4 | 100 HB | 98.5 % IACS |
Spring hard | Spring-temper strip/wire for contacts, gaskets and RF fingers where elastic limit matters more than ductility. | 350 | 380 | 4 | 105 HB | 98 % IACS |
Extra spring hard | Maximum cold-worked strength available in thin OF copper foil/strip; essentially flat-form only. | 365 | 393 | 3 | 110 HB | 98 % IACS |
What is C10200-M20?
C10200-M20 is C10200 supplied in the M20 condition — mill condition for thick plate, billet and heavy busbar that will be machined or annealed afterwards. C10200-M20 has a yield strength of 75 MPa (10.9 ksi) and a tensile strength of 220 MPa (31.9 ksi) — weaker than 91% of copper alloy grades. Elongation at break is 45% and the elastic modulus is 117 GPa (17 Msi). C10200-M20 has a density of 8.94 g/cm³ (0.323 lb/in³), heavier than 90% of copper alloy grades. It melts at 1,083°C (1,981 °F). O is the default condition FabDigit quotes; M20 is available on request or by drawing note.
Advantages
- Conducts heat well — 391 W/m·K (225.9 BTU/hr·ft·°F), better than 98% of copper alloy grades
- High electrical conductivity — 101 % IACS, better than 98% of copper alloy grades
- Forms and bends easily — 95/100, better than 94% of copper alloy grades
- Ductile — tolerates forming and impact — 45%, better than 91% of copper alloy grades
- Readily welded — 65/100, better than 80% of copper alloy grades
Limitations
- Difficult to machine — 20/100, worse than 98% of copper alloy grades
- Low strength — 75 MPa (10.9 ksi), worse than 91% of copper alloy grades
C10200-M20 properties
Typical room-temperature values for C10200-M20; 19 are specific to this condition. Other listed values are C10200 reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
C10200-M20 has a density of 8.94 g/cm³ (0.323 lb/in³), heavier than 90% of copper alloy grades. It melts at 1,083°C (1,981 °F).
Mechanical12
C10200-M20 has a yield strength of 75 MPa (10.9 ksi) and a tensile strength of 220 MPa (31.9 ksi) — weaker than 91% of copper alloy grades. Elongation at break is 45% and the elastic modulus is 117 GPa (17 Msi).
Thermal6
C10200-M20 is rated for continuous service to 200°C (392 °F). It conducts heat at 391 W/m·K (225.9 BTU/hr·ft·°F), better than 98% of copper alloy grades. Thermal expansion is 16.9 µm/m·K (9.39 µin/in·°F).
Electrical3
C10200-M20 conducts electricity at 101 % IACS, better than 98% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is very good (70/100), better than 76% of copper alloy grades.
Sustainability4
Producing a kilogram of C10200-M20 takes about 57 MJ of energy and emits 3.8 kg of CO₂ — less than 52% of copper alloy grades. Typical recycled content is 20%.
Manufacturability8
C10200-M20's machinability is poor (20/100, worse than 98% of copper alloy grades); weldability good (65/100); formability excellent (95/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with C10200-M20
Is C10200 easy to machine?
Gummy and stringy — use sharp positive-rake tools, high speed, generous soluble-oil coolant and H02/H04 temper (never annealed) for acceptable chip break; rating ~20 % of free-cutting brass.
Can C10200 be welded?
GTAW/GMAW with ERCu filler, helium or Ar-He shielding and 200–400 °C preheat on thick sections to overcome the heat sink; no hydrogen embrittlement risk, so brazing and hydrogen-furnace brazing are excellent.
Can C10200 be formed, bent or molded?
Outstanding cold formability in O temper (deep draw, coin, spin, roll-form); interanneal at 375–650 °C when total reduction exceeds ~60 %.
What surface finishes work on C10200?
Not anodisable — bright-dip/pickle then electroplate Ni, Ag, Sn or Au, or apply benzotriazole passivation/clear lacquer; polishes to a high mirror finish but tarnishes quickly if unprotected.
C10200 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 |
|---|---|---|
| O10 ppm max — defines the 'oxygen-free' grade | ≤ 0 | 5×10⁻⁴ |
| Pnot deliberately added (deoxidiser-free to preserve conductivity) | ≤ 3×10⁻⁴ | — |
| Agcounted as copper | ≈ 0 | 0 |
| Total other impuritiesBi, Pb, S, Se, Te, Sb, As, Fe, Ni, Sn, Zn each held to ppm levels per ASTM B170 | ≤ 0.05 | — |
| CuCu + Ag, oxygen-free; ASTM B170 Grade 2 / UNS C10200 | ≥ 99.95 (balance) | — |
C10200-M20 — frequently asked
What is C10200-M20 used for?
C10200-M20 is typically used for electrical conductors and bus bars, RF cavities and waveguides, vacuum chamber components and seals, hydrogen-brazed heat exchangers, heat sinks and cold plates and transformer and switchgear terminals. In short: oxygen-free pure copper.
What is the yield strength of C10200-M20?
C10200-M20 has a typical yield strength of 75 MPa (10.9 ksi) and a tensile strength of 220 MPa (31.9 ksi) — weaker than 91% of copper alloy grades. Strength varies by condition: see the 14 listed tempers.
Is C10200-M20 easy to machine?
Not especially — machinability is rated poor (20/100, worse than 98% of copper alloy grades). Gummy and stringy — use sharp positive-rake tools, high speed, generous soluble-oil coolant and H02/H04 temper (never annealed) for acceptable chip break; rating ~20 % of free-cutting brass.
Can C10200-M20 be welded?
Yes — weldability is rated good (65/100). GTAW/GMAW with ERCu filler, helium or Ar-He shielding and 200–400 °C preheat on thick sections to overcome the heat sink; no hydrogen embrittlement risk, so brazing and hydrogen-furnace brazing are excellent.
What surface finishes work on C10200-M20?
Not anodisable — bright-dip/pickle then electroplate Ni, Ag, Sn or Au, or apply benzotriazole passivation/clear lacquer; polishes to a high mirror finish but tarnishes quickly if unprotected.
Can C10200-M20 be formed, bent or molded?
Outstanding cold formability in O temper (deep draw, coin, spin, roll-form); interanneal at 375–650 °C when total reduction exceeds ~60 %.
What is the maximum service temperature of C10200-M20?
C10200-M20 is rated for continuous use to about 200°C (392 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between C10200-O and C10200-H10?
O is the default condition — most stocked condition: maximum ductility and conductivity for deep drawing, bending, gaskets, vacuum parts and busbar forming. H10: maximum cold-worked strength available in thin OF copper foil/strip; essentially flat-form only. Yield strength is 69 MPa in O versus 365 MPa in H10.
Can FabDigit make parts in C10200-M20?
Yes — C10200-M20 is available for CNC machining and sheet metal with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- ASTM B170 — Oxygen-Free Electrolytic Copper Refinery Shapes — ASTM International (2019)
- ASTM B152/B152M — Copper Sheet, Strip, Plate and Rolled Bar — ASTM International (2019)
- ASTM B187 — Copper Bus Bar, Rod and Shapes — ASTM International (2020)
- EN 13601 / EN 1976 — Cu-OF (CW008A) — CEN (2013)
- CDA/copper.org alloy datasheet C10200 — Copper Development Association (2024)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous 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.