FabDigitFabDigit

Copper Alloy C81200-M06

Finish state

UNS C81200 · ASTM B824, B369

M06 = as investment cast

Choose for thin, intricate contact/terminal shapes where machining allowance must be minimal.

High cost $$$$

Values for the M06 condition

Other C81200 tempers and conditions

C81200 is listed in 6 conditions; see the grade overview at C81200.

Compare all 6 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
Annealed
Use after heavy weld repair or straightening to restore maximum conductivity and remove residual stress.551654540 HB84 % IACS
M01Default
As sand cast
Standard stocked/produced condition for one-off and small-lot electrical castings.621724044 HB80 % IACS
M06This page
As investment cast
Choose for thin, intricate contact/terminal shapes where machining allowance must be minimal.621703844 HB80 % IACS
As centrifugally cast
Pick for rings, bushings and tubular electrical bodies needing dense, porosity-free walls.651854046 HB82 % IACS
As plaster cast
Medium-volume parts; finer chill grain gives slightly higher strength and better surface than sand.681853848 HB80 % IACS
As continuous cast
Best choice when buying bar/tube stock for machined electrical parts — densest, most uniform structure.752003550 HB82 % IACS

What is C81200-M06?

C81200-M06 is C81200 supplied in the M06 condition — choose for thin, intricate contact/terminal shapes where machining allowance must be minimal. C81200-M06 has a yield strength of 62 MPa (8.99 ksi) and a tensile strength of 170 MPa (24.7 ksi) — weaker than 99% of copper alloy grades. Elongation at break is 38% and the elastic modulus is 112 GPa (16.2 Msi). C81200-M06 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). M01 is the default condition FabDigit quotes; M06 is available on request or by drawing note.

Advantages

  • 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
  • Ductile — tolerates forming and impact — 38%, better than 82% 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-M06 properties

Typical room-temperature values for C81200-M06; 19 are specific to this condition. Other listed values are C81200 reference data and may not represent this condition. Bars are the position among copper alloy grades.

Physical3

C81200-M06 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).

Density8.91 g/cm³0.32 lb/in³
Melting Point (Solidus)1,065°C1,949 °F
Liquidus Temperature1,083°C1,981 °F

Mechanical13

C81200-M06 has a yield strength of 62 MPa (8.99 ksi) and a tensile strength of 170 MPa (24.7 ksi) — weaker than 99% of copper alloy grades. Elongation at break is 38% and the elastic modulus is 112 GPa (16.2 Msi).

Elastic (Young's) Modulus112 GPa16.2 Msi
Shear Modulus42 GPa6.1 Msi
Bulk Modulus138 GPa20 Msi
Poisson's Ratio0.34
Tensile Strength (Ultimate)170 MPa24.7 ksi
Yield Strength (0.2% offset)62 MPa9 ksi
Elongation at Break38%
Reduction in Area33%
Shear Strength124 MPa18 ksi
Fatigue Strength (Endurance Limit)60 MPa8.7 ksi
Charpy V-Notch Impact (RT)42 J31 ft·lbf
Hardness, Brinell44 HB
Hardness, Vickers46 HV

Thermal6

C81200-M06 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).

Thermal Conductivity320 W/m·K185 BTU/hr·ft·°F
Specific Heat Capacity385 J/kg·K0.09 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)17.6 µm/m·K9.8 µin/in·°F
Latent Heat of Fusion205 J/g88.1 BTU/lb
Max Service Temperature (continuous)200°C392 °F
Min Service Temperature-200°C-328 °F

Electrical3

C81200-M06 conducts electricity at 80 % IACS, better than 84% of copper alloy grades.

Electrical Conductivity80 % IACS
Electrical Resistivity2.16×10⁻⁸ Ω·m0.85 µΩ·in
Magnetic Responsenon-magnetic

Chemical & Environmental3

Corrosion resistance is good (65/100), better than 58% of copper alloy grades.

Galvanic Potential (seawater, vs SCE)-0.2 V
Corrosion ResistanceGood65/100
Chemical Resistance SummaryGood in atmosphere, fresh and low-velocity seawater, neutral salts, non-oxidizing acids and most organics; attacked by ammonia/amines (stress-corrosion risk), sulfides, nitric acid, oxidizing acids and strong oxidizers.

Sustainability4

Producing a kilogram of C81200-M06 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%.

Embodied Energy (primary production)55 MJ/kg23,646 BTU/lb
Embodied Carbon (primary production)3.6 kg CO₂/kg
Embodied Water250 L/kg30 gal/lb
Typical Recycled Content50%

Manufacturability8

C81200-M06's machinability is poor (25/100, worse than 86% of copper alloy grades); weldability good (65/100); formability poor (30/100).

MachinabilityPoor25/100
Machinability Rating (AISI 1212 = 100 %)20%
WeldabilityGood65/100
Formability (cold)Poor30/100
CastabilityGood60/100
Brazeability / SolderabilityExcellent90/100
PolishabilityVery good70/100
Anodizing Responsen/a — copper alloy is not anodized; use electroplating (Ni/Sn/Ag), chemical patina or clear lacquer

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

Working with C81200-M06

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.

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.

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.

ElementSpec limit (wt %)Nominal
Pdeoxidant residual — controls gas soundness and weldability0.05 – 0.070.06
CuCu + Ag, 99.9 % min; remainder is the phosphorus residual and trace impurities≥ 99.9 (balance)—

C81200-M06 — frequently asked

What is C81200-M06 used for?

C81200-M06 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-M06?

C81200-M06 has a typical yield strength of 62 MPa (8.99 ksi) and a tensile strength of 170 MPa (24.7 ksi) — weaker than 99% of copper alloy grades. Strength varies by condition: see the 6 listed tempers.

Is C81200-M06 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-M06 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-M06?

Not anodizable; specify electroplating (Ni, Sn, Ag) for contacts, mechanical polishing or a chemical patina, and clear lacquer to stop atmospheric tarnish.

Can C81200-M06 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-M06?

C81200-M06 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.

Sources

  1. ASTM B824 — Standard Specification for General Requirements for Copper Alloy Castings — ASTM International (2022)
  2. Cast Copper Alloy UNS C81200 alloy data (Standards Handbook — Cast Copper and Copper Alloy Products) — Copper Development Association (copper.org) (2022)
  3. ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials — ASM International (1990)
  4. ASM Specialty Handbook: Copper and Copper Alloys — ASM International (2001)

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.