Copper Alloy C62300-M20
Finish state
UNS C62300 · ASTM B150, B169
M20 = as hot rolled
Standard condition for ASTM B169 plate and flat bar used for wear plates, gibs and machined structural parts.
Values for the M20 condition
Other C62300 tempers and conditions
C62300 is listed in 7 conditions; see the grade overview at C62300.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Soft annealed | Less common softened condition used to recover some ductility before limited forming or as a starting point for redrawing. | 215 | 515 | 32 | 135 HB | 12 % IACS |
As hot forged and air cooled | Pick for forged flanges, valve bodies and near-net shapes where uniform properties through thick sections matter more than peak strength. | 255 | 565 | 25 | 150 HB | — |
M20This page As hot rolled | Standard condition for ASTM B169 plate and flat bar used for wear plates, gibs and machined structural parts. | 275 | 585 | 22 | 155 HB | — |
M30Default As hot extruded | The default stocked condition: hot-extruded rod and shapes with a good strength/ductility balance for general machining. | 290 | 585 | 25 | 160 HB | 12 % IACS |
Drawn and stress relieved | Choose when high yield strength must be combined with dimensional stability after machining (valve stems, pump shafts, studs). | 415 | 655 | 15 | 180 HB | — |
Quench hardened and temper annealed | Heat-treated condition for maximum hardness and wear resistance in bearings, wear rings and forming dies; ductility is reduced. | 415 | 690 | 14 | 17 HRC | — |
Full hard | Cold-drawn small-diameter bar for shafts and fasteners needing higher yield strength and better surface finish; residual stress remains. | 435 | 655 | 12 | 187 HB | — |
What is C62300-M20?
C62300-M20 is C62300 supplied in the M20 condition — standard condition for ASTM B169 plate and flat bar used for wear plates, gibs and machined structural parts. C62300-M20 has a yield strength of 275 MPa (39.9 ksi) and a tensile strength of 585 MPa (84.8 ksi) — stronger than 57% of copper alloy grades. Elongation at break is 22% and the elastic modulus is 117 GPa (17 Msi). C62300-M20 has a density of 7.65 g/cm³ (0.276 lb/in³), lighter than 91% of copper alloy grades. It melts at 1,040°C (1,904 °F). M30 is the default condition FabDigit quotes; M20 is available on request or by drawing note.
Advantages
- Lightweight — 7.65 g/cm³ (0.276 lb/in³), better than 91% of copper alloy grades
- High service temperature — 300°C (572 °F), better than 85% of copper alloy grades
- Readily welded — 70/100, better than 85% of copper alloy grades
- Good corrosion resistance — 72/100, better than 84% of copper alloy grades
Limitations
- Poor heat conductor — 39.8 W/m·K (23 BTU/hr·ft·°F), worse than 83% of copper alloy grades
C62300-M20 properties
Typical room-temperature values for C62300-M20; 10 are specific to this condition. Other listed values are C62300 reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
C62300-M20 has a density of 7.65 g/cm³ (0.276 lb/in³), lighter than 91% of copper alloy grades. It melts at 1,040°C (1,904 °F).
Mechanical13
C62300-M20 has a yield strength of 275 MPa (39.9 ksi) and a tensile strength of 585 MPa (84.8 ksi) — stronger than 57% of copper alloy grades. Elongation at break is 22% and the elastic modulus is 117 GPa (17 Msi).
Thermal6
C62300-M20 is rated for continuous service to 300°C (572 °F). It conducts heat at 39.8 W/m·K (23 BTU/hr·ft·°F), worse than 83% of copper alloy grades. Thermal expansion is 16.2 µm/m·K (9 µin/in·°F).
Electrical3
C62300-M20 conducts electricity at 12 % IACS, worse than 62% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is very good (72/100), better than 84% of copper alloy grades.
Sustainability4
Producing a kilogram of C62300-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 40%.
Manufacturability8
C62300-M20's machinability is fair (45/100, better than 64% of copper alloy grades); weldability very good (70/100); formability poor (30/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with C62300-M20
Is C62300 easy to machine?
Machines like a tough medium-strength bronze at roughly half the rate of free-cutting brass: use rigid setups, sharp carbide, positive rake, moderate speed with high feed and flood coolant to avoid work-hardened glazing.
Can C62300 be welded?
GTAW/GMAW with aluminium-bronze filler (ERCuAl-A2) works well; keep interpass temperature low, remove the tenacious alumina film mechanically and avoid oxyacetylene welding and soft soldering.
Can C62300 be formed, bent or molded?
Hot work at 750–900 °C (forge, extrude, hot bend); cold formability is poor, so limit cold bending and stress-relieve at 400–500 °C after drawing or heavy machining.
What surface finishes work on C62300?
Not anodisable; takes a bright golden polish, can be buffed, shot-peened for fatigue life, or chemically darkened. Nickel/chrome plating requires careful activation of the oxide film.
C62300 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 |
|---|---|---|
| Al | 8.5 – 11 | 9.3 |
| Fegrain refinement, κ-phase former | 2 – 4 | 3 |
| NiNi + Co counted together | ≤ 1 | — |
| Mn | ≤ 0.5 | — |
| Sn | ≤ 0.6 | — |
| Si | ≤ 0.25 | — |
| Curemainder, Cu + named elements ≥ 99.5 % | ≥ 82.2 (balance) | — |
C62300-M20 — frequently asked
What is C62300-M20 used for?
C62300-M20 is typically used for gears, bearings, marine hardware, wear plates and valve stems. In short: best-machining aluminum bronze; gear and bearing bronze; highest conductivity in series.
What is the yield strength of C62300-M20?
C62300-M20 has a typical yield strength of 275 MPa (39.9 ksi) and a tensile strength of 585 MPa (84.8 ksi) — stronger than 57% of copper alloy grades. Strength varies by condition: see the 7 listed tempers.
Is C62300-M20 easy to machine?
Reasonably — machinability is rated fair (45/100, better than 64% of copper alloy grades). Machines like a tough medium-strength bronze at roughly half the rate of free-cutting brass: use rigid setups, sharp carbide, positive rake, moderate speed with high feed and flood coolant to avoid work-hardened glazing.
Can C62300-M20 be welded?
Yes — weldability is rated very good (70/100). GTAW/GMAW with aluminium-bronze filler (ERCuAl-A2) works well; keep interpass temperature low, remove the tenacious alumina film mechanically and avoid oxyacetylene welding and soft soldering.
What surface finishes work on C62300-M20?
Not anodisable; takes a bright golden polish, can be buffed, shot-peened for fatigue life, or chemically darkened. Nickel/chrome plating requires careful activation of the oxide film.
Can C62300-M20 be formed, bent or molded?
Hot work at 750–900 °C (forge, extrude, hot bend); cold formability is poor, so limit cold bending and stress-relieve at 400–500 °C after drawing or heavy machining.
What is the maximum service temperature of C62300-M20?
C62300-M20 is rated for continuous use to about 300°C (572 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between C62300-M30 and C62300-H04?
M30 is the default condition — the default stocked condition: hot-extruded rod and shapes with a good strength/ductility balance for general machining. H04: cold-drawn small-diameter bar for shafts and fasteners needing higher yield strength and better surface finish; residual stress remains. Yield strength is 290 MPa in M30 versus 435 MPa in H04.
Sources
- ASTM B150/B150M — Aluminum Bronze Rod, Bar, and Shapes — ASTM International (2019)
- ASTM B169/B169M — Aluminum Bronze Plate, Sheet, Strip and Rolled Bar — ASTM International (2019)
- CDA Alloy Datasheet C62300 (copper.org) — Copper Development Association (2023)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- GB/T 1176 / GB/T 4423 QAl9-4 — SAC (2020)
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.