Copper Alloy C81200
UNS C81200 · ASTM B824, B369
C81200 is a cast copper-chromium alloy (CuCr1-C, ASTM B824/B369) with a lower chromium content than C81500, precipitation hardenable to combine moderate strength with high conductivity.
Reference datasheet — C81200 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the M01 condition
C81200 tempers and conditions
C81200 is supplied in 6 conditions, soft to hard. M01 is the default FabDigit quotes; the values on this page are for it.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Use after heavy weld repair or straightening to restore maximum conductivity and remove residual stress. | 55 | 165 | 45 | 40 HB | 84 % IACS |
M01Default As sand cast | Standard stocked/produced condition for one-off and small-lot electrical castings. | 62 | 172 | 40 | 44 HB | 80 % IACS |
As investment cast | Choose for thin, intricate contact/terminal shapes where machining allowance must be minimal. | 62 | 170 | 38 | 44 HB | 80 % IACS |
As centrifugally cast | Pick for rings, bushings and tubular electrical bodies needing dense, porosity-free walls. | 65 | 185 | 40 | 46 HB | 82 % IACS |
As plaster cast | Medium-volume parts; finer chill grain gives slightly higher strength and better surface than sand. | 68 | 185 | 38 | 48 HB | 80 % IACS |
As continuous cast | Best choice when buying bar/tube stock for machined electrical parts — densest, most uniform structure. | 75 | 200 | 35 | 50 HB | 82 % IACS |
What is C81200?
C81200 is a cast copper-chromium alloy (CuCr1-C, ASTM B824/B369) with a lower chromium content than C81500, precipitation hardenable to combine moderate strength with high conductivity. It is poured as sand, permanent-mold and centrifugal castings for resistance-welding hardware, mold inserts and conductive structural parts. Reference values are 62 MPa yield, 172 MPa tensile, 40 % elongation, 44 HB, 80 % IACS and 320 W/m·K, with service to 200 °C. Strength is modest for a cast high-copper alloy, so step up to C81500 or the Cr-Ni-Si grade C81540 when load or wear governs. C81200 has a density of 8.91 g/cm³ (0.322 lb/in³), heavier than 80% of copper alloy grades. It melts at 1,065°C (1,949 °F). C81200 has a yield strength of 62 MPa (8.99 ksi) and a tensile strength of 172 MPa (24.9 ksi) — weaker than 99% of copper alloy grades. Elongation at break is 40% and the elastic modulus is 112 GPa (16.2 Msi).
What is C81200 used for?
- resistance welding electrode holders
- mold inserts
- high-conductivity structural castings
Advantages
- Ductile — tolerates forming and impact — 40%, better than 84% 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
- Readily welded — 65/100, better than 80% of copper alloy grades
Limitations
- Low strength — 62 MPa (8.99 ksi), worse than 99% of copper alloy grades
- Difficult to machine — 25/100, worse than 86% of copper alloy grades
C81200 properties
Typical room-temperature values for C81200-M01; bars are the position among copper alloy grades.
Physical3
C81200 has a density of 8.91 g/cm³ (0.322 lb/in³), heavier than 80% of copper alloy grades. It melts at 1,065°C (1,949 °F).
Mechanical13
C81200 has a yield strength of 62 MPa (8.99 ksi) and a tensile strength of 172 MPa (24.9 ksi) — weaker than 99% of copper alloy grades. Elongation at break is 40% and the elastic modulus is 112 GPa (16.2 Msi).
Thermal6
C81200 is rated for continuous service to 200°C (392 °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 17.6 µm/m·K (9.78 µin/in·°F).
Electrical3
C81200 conducts electricity at 80 % IACS, better than 84% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is good (65/100), better than 58% of copper alloy grades.
Sustainability4
Producing a kilogram of C81200 takes about 55 MJ of energy and emits 3.6 kg of CO₂ — less than 72% of copper alloy grades. Typical recycled content is 50%.
Manufacturability8
C81200's machinability is poor (25/100, worse than 86% of copper alloy grades); weldability good (65/100); formability poor (30/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the copper alloy family
Yield strength against density for every copper alloy grade FabDigit runs. C81200 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with C81200
Is C81200 easy to machine?
Gummy and stringy like pure copper (~20 % of AISI 1212): use sharp positive-rake tools, high speed, light-to-moderate feed, generous coolant; avoid dwelling to prevent smearing.
Can C81200 be welded?
Excellent for a copper — the P residual prevents steam/hydrogen embrittlement, so GTAW/GMAW with ERCu filler, high preheat (300–500 °C) and helium-rich shielding gives sound repair welds.
Can C81200 be formed, bent or molded?
Foundry alloy: needs large risers, chills and clean charge because of copper's high shrinkage and gas pickup; not intended for cold forming beyond light coining/straightening.
C81200 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 |
|---|---|---|
| Pdeoxidant residual — controls gas soundness and weldability | 0.05 – 0.07 | 0.06 |
| CuCu + Ag, 99.9 % min; remainder is the phosphorus residual and trace impurities | ≥ 99.9 (balance) |
What surface finishes work on C81200?
Not anodizable; specify electroplating (Ni, Sn, Ag) for contacts, mechanical polishing or a chemical patina, and clear lacquer to stop atmospheric tarnish.
Surface treatments FabDigit runs on copper alloy parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Equivalent designations
Standards and trade names that resolve to Copper Alloy C81200 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- B824B369
- Similar grades
- CC140CCuCr1-C
How much does C81200 cost?
C81200 is a high-cost copper alloy ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
C81200 — frequently asked
What is C81200 used for?
C81200 is typically used for resistance welding electrode holders, mold inserts and high-conductivity structural castings. In short: high-conductivity cast copper; weld-repairable copper casting; age-hardenable Cu-Cr grade.
What is the yield strength of C81200?
C81200 has a typical yield strength of 62 MPa (8.99 ksi) and a tensile strength of 172 MPa (24.9 ksi) — weaker than 99% of copper alloy grades. Strength varies by condition: see the 6 listed tempers.
Is C81200 easy to machine?
Not especially — machinability is rated poor (25/100, worse than 86% of copper alloy grades). Gummy and stringy like pure copper (~20 % of AISI 1212): use sharp positive-rake tools, high speed, light-to-moderate feed, generous coolant; avoid dwelling to prevent smearing.
Can C81200 be welded?
Yes — weldability is rated good (65/100). Excellent for a copper — the P residual prevents steam/hydrogen embrittlement, so GTAW/GMAW with ERCu filler, high preheat (300–500 °C) and helium-rich shielding gives sound repair welds.
What surface finishes work on C81200?
Not anodizable; specify electroplating (Ni, Sn, Ag) for contacts, mechanical polishing or a chemical patina, and clear lacquer to stop atmospheric tarnish.
Can C81200 be formed, bent or molded?
Foundry alloy: needs large risers, chills and clean charge because of copper's high shrinkage and gas pickup; not intended for cold forming beyond light coining/straightening.
What is the maximum service temperature of C81200?
C81200 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 C81200-M01 and C81200-M07?
M01 is the default condition — standard stocked/produced condition for one-off and small-lot electrical castings. M07: best choice when buying bar/tube stock for machined electrical parts — densest, most uniform structure. Yield strength is 62 MPa in M01 versus 75 MPa in M07.
How much does C81200 cost?
C81200 is a high-cost copper alloy ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- ASTM B824 — Standard Specification for General Requirements for Copper Alloy Castings — ASTM International (2022)
- Cast Copper Alloy UNS C81200 alloy data (Standards Handbook — Cast Copper and Copper Alloy Products) — Copper Development Association (copper.org) (2022)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials — ASM International (1990)
- ASM Specialty Handbook: Copper and Copper Alloys — ASM International (2001)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.