Copper Alloy C12600-M20
Finish state
UNS C12600
M20 = as hot rolled
Cheapest mill condition for thick plate, bus bar blanks and hot-extruded shapes where softness is acceptable.
Values for the M20 condition
Other C12600 tempers and conditions
C12600 is listed in 15 conditions; see the grade overview at C12600.
Compare all 15 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Soft annealed | Choose for deep drawing, spinning, tight bending, gaskets and flexible braid/laminated bus. | 70 | 220 | 45 | 45 HB | 98 % IACS |
M20This page As hot rolled | Cheapest mill condition for thick plate, bus bar blanks and hot-extruded shapes where softness is acceptable. | 75 | 225 | 45 | 45 HB | 98 % IACS |
Annealed to 0.050 mm grain size | Grain-size-controlled soft sheet/strip for severe drawing without orange peel. | 76 | 230 | 45 | 45 HB | 98 % IACS |
Annealed to 0.025 mm grain size | Fine-grain soft strip for shallow forming with better surface finish and slightly higher strength. | 85 | 240 | 42 | 50 HB | 98 % IACS |
1/8 hard | Slight stiffening while keeping most of the soft-temper formability (roofing, flashing, formed bus). | 195 | 250 | 30 | 65 HB | 97 % IACS |
Light drawn | Tube temper giving some stiffness while still allowing bending and flaring. | 195 | 250 | 25 | 65 HB | 97 % IACS |
Quarter hard | Good balance of bendability and stiffness for brackets, terminals and light formed parts. | 205 | 260 | 25 | 75 HB | 97 % IACS |
Drawn, general purpose | Standard hard-drawn tube condition for straight-length plumbing and pressure lines. | 220 | 280 | 20 | 80 HB | 97 % IACS |
Half hard | Most common stocked strip/plate temper when moderate strength plus some bending is needed. | 250 | 290 | 14 | 85 HB | 97 % IACS |
Three-quarter hard | Intermediate step where H02 is too soft but full hard would crack on the required bend. | 275 | 315 | 10 | 90 HB | 97 % IACS |
H04Default Full hard | Default stock condition for bus bar, rod, hard-drawn wire and plate needing strength and stiffness with minimal forming. | 310 | 345 | 6 | 95 HB | 97 % IACS |
Extra hard | For flat springs, clips and contacts where higher yield matters more than ductility. | 340 | 365 | 5 | 100 HB | 96 % IACS |
Spring hard | Maximum practical strength in strip form for spring contacts and shielding fingers. | 350 | 380 | 4 | 105 HB | 96 % IACS |
Extra spring hard | Heaviest cold reduction offered on strip; bend only along, not across, the rolling direction. | 365 | 395 | 4 | 108 HB | 96 % IACS |
Hard drawn | Heavily drawn wire/rod for overhead conductors, grounding conductors and stranded cable. | 380 | 415 | 2 | 110 HB | 96 % IACS |
What is C12600-M20?
C12600-M20 is C12600 supplied in the M20 condition — cheapest mill condition for thick plate, bus bar blanks and hot-extruded shapes where softness is acceptable. C12600-M20 has a yield strength of 75 MPa (10.9 ksi) and a tensile strength of 225 MPa (32.6 ksi) — weaker than 91% of copper alloy grades. Elongation at break is 45% and the elastic modulus is 115 GPa (16.7 Msi). C12600-M20 has a density of 8.94 g/cm³ (0.323 lb/in³), heavier than 90% of copper alloy grades. It melts at 1,065°C (1,949 °F). H04 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 — 98 % IACS, better than 94% of copper alloy grades
- Ductile — tolerates forming and impact — 45%, better than 91% of copper alloy grades
- Forms and bends easily — 88/100, better than 87% 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
C12600-M20 properties
Typical room-temperature values for C12600-M20; 19 are specific to this condition. Other listed values are C12600 reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
C12600-M20 has a density of 8.94 g/cm³ (0.323 lb/in³), heavier than 90% of copper alloy grades. It melts at 1,065°C (1,949 °F).
Mechanical12
C12600-M20 has a yield strength of 75 MPa (10.9 ksi) and a tensile strength of 225 MPa (32.6 ksi) — weaker than 91% of copper alloy grades. Elongation at break is 45% and the elastic modulus is 115 GPa (16.7 Msi).
Thermal6
C12600-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 17.7 µm/m·K (9.83 µin/in·°F).
Electrical3
C12600-M20 conducts electricity at 98 % IACS, better than 94% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is good (60/100), worse than 68% of copper alloy grades.
Sustainability4
Producing a kilogram of C12600-M20 takes about 55 MJ of energy and emits 3.8 kg of CO₂ — less than 72% of copper alloy grades. Typical recycled content is 45%.
Manufacturability7
C12600-M20's machinability is poor (20/100, worse than 98% of copper alloy grades); weldability fair (35/100); formability excellent (88/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with C12600-M20
Is C12600 easy to machine?
Gummy and low rated (~20 % of AISI 1212): use sharp positive-rake tools, high speed, generous coolant and chip breakers; consider C14500/C36000 if heavy machining is required.
Can C12600 be welded?
Oxygen-bearing copper is prone to hydrogen embrittlement and porosity — prefer GTAW/GMAW with deoxidized filler (ERCu), preheat 200–500 °C on thick sections, and avoid reducing/H2 atmospheres above ~370 °C; brazing and soldering are excellent.
Can C12600 be formed, bent or molded?
Outstanding cold formability in O60/OS tempers (deep drawing, spinning, roll forming); interstage anneal at 400–600 °C when reduction exceeds ~60 %.
What surface finishes work on C12600?
Cannot be anodized; polishes to a bright finish but tarnishes — protect with clear lacquer/benzotriazole, or tin, nickel or silver plate for contacts and bus joints.
C12600 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 |
|---|---|---|
| Ocuprous oxide present as dispersed Cu2O; not usually a spec limit | 0.02 – 0.05 | 0.04 |
| Sbimpurity limit, typical FRTP practice | ≤ 0 | — |
| Asimpurity limit | ≤ 0.01 | — |
| Biimpurity limit | ≤ 0 | — |
| Pbimpurity limit | ≤ 0.01 | — |
| Feimpurity limit | ≤ 0.03 | — |
| Niimpurity limit | ≤ 0.05 | — |
| Simpurity limit | ≤ 0 | — |
| CuCu + Ag, remainder; fire-refined tough pitch, oxygen-bearing | ≥ 99.9 (balance) | — |
C12600-M20 — frequently asked
What is C12600-M20 used for?
C12600-M20 is typically used for wire products, general fabrication and roofing sheet. In short: tighter purity than C12500; 97 % IACS commercial copper; wide temper range on file.
What is the yield strength of C12600-M20?
C12600-M20 has a typical yield strength of 75 MPa (10.9 ksi) and a tensile strength of 225 MPa (32.6 ksi) — weaker than 91% of copper alloy grades. Strength varies by condition: see the 15 listed tempers.
Is C12600-M20 easy to machine?
Not especially — machinability is rated poor (20/100, worse than 98% of copper alloy grades). Gummy and low rated (~20 % of AISI 1212): use sharp positive-rake tools, high speed, generous coolant and chip breakers; consider C14500/C36000 if heavy machining is required.
Can C12600-M20 be welded?
With care — weldability is rated fair (35/100). Oxygen-bearing copper is prone to hydrogen embrittlement and porosity — prefer GTAW/GMAW with deoxidized filler (ERCu), preheat 200–500 °C on thick sections, and avoid reducing/H2 atmospheres above ~370 °C; brazing and soldering are excellent.
What surface finishes work on C12600-M20?
Cannot be anodized; polishes to a bright finish but tarnishes — protect with clear lacquer/benzotriazole, or tin, nickel or silver plate for contacts and bus joints.
Can C12600-M20 be formed, bent or molded?
Outstanding cold formability in O60/OS tempers (deep drawing, spinning, roll forming); interstage anneal at 400–600 °C when reduction exceeds ~60 %.
What is the maximum service temperature of C12600-M20?
C12600-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 C12600-H04 and C12600-O60?
H04 is the default condition — default stock condition for bus bar, rod, hard-drawn wire and plate needing strength and stiffness with minimal forming. O60: choose for deep drawing, spinning, tight bending, gaskets and flexible braid/laminated bus. Yield strength is 310 MPa in H04 versus 70 MPa in O60.
Sources
- ASTM B152/B152M — Copper Sheet, Strip, Plate and Rolled Bar — ASTM International (2019)
- ASTM B187/B187M — Copper Bus Bar, Rod and Shapes — ASTM International (2020)
- ASTM B49 — Copper Rod for Electrical Purposes — ASTM International (2020)
- CDA Standard Designations for Wrought and Cast Copper and Copper Alloys (C1xxxx series datasheets) — Copper Development Association (2023)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials — 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.