Copper Alloy C67300
UNS C67300 · ASTM B138
C67300 is a high-strength manganese brass, traditionally called a manganese bronze, with lead added for machinability and covered by ASTM B138.
Reference datasheet — C67300 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 M30 condition
C67300 tempers and conditions
C67300 is supplied in 5 conditions, soft to hard. M30 is the default FabDigit quotes; the values on this page are for it.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Soft annealed | Use when maximum ductility for bending, staking or secondary forming is needed. | 215 | 490 | 33 | 115 HB | 12 % IACS |
As forged and quenched | Choose for near-net-shape marine hardware and valve bodies produced by hot die forging. | 290 | 570 | 25 | 140 HB | 12 % IACS |
M30Default As hot extruded | Standard stocked condition for rod, bar and shapes; best combination of strength, ductility and machinability. | 310 | 600 | 22 | 150 HB | 12 % IACS |
Half hard | Cold-drawn condition for close tolerance shafts, stems and gear blanks needing higher yield strength. | 415 | 640 | 18 | 170 HB | 12 % IACS |
Full hard | Maximum-strength drawn bar for heavily loaded pins, wear parts and fasteners; very limited ductility. | 480 | 700 | 12 | 190 HB | 12 % IACS |
What is C67300?
C67300 is a high-strength manganese brass, traditionally called a manganese bronze, with lead added for machinability and covered by ASTM B138. It is supplied as rod, bar and hot-forged shapes in M30, M11, O60, H02 and H04 conditions and delivers 310 MPa yield, 600 MPa tensile, 22 % elongation and 150 HB (82 HRB) with service to 200 °C, which suits marine hardware, gears and heavily loaded fittings. Machinability is about 75 % of C36000 and conductivity is 12 % IACS. Cold forming is limited and fusion welding is not recommended; use C46400 naval brass where welding or cold bending is required. C67300 has a density of 8.19 g/cm³ (0.296 lb/in³), lighter than 85% of copper alloy grades. It melts at 855°C (1,571 °F). C67300 has a yield strength of 310 MPa (45 ksi) and a tensile strength of 600 MPa (87 ksi) — stronger than 64% of copper alloy grades. Elongation at break is 22% and the elastic modulus is 103 GPa (14.9 Msi).
What is C67300 used for?
- marine propeller hubs
- gears
- valve stems
- heavy-duty fittings
Advantages
- Low embodied carbon — 3.3 kg CO₂/kg, better than 90% of copper alloy grades
- Easy to machine — 75/100, better than 80% of copper alloy grades
Limitations
- Difficult to weld — 20/100, worse than 88% of copper alloy grades
C67300 properties
Typical room-temperature values for C67300-M30; bars are the position among copper alloy grades.
Physical3
C67300 has a density of 8.19 g/cm³ (0.296 lb/in³), lighter than 85% of copper alloy grades. It melts at 855°C (1,571 °F).
Mechanical12
C67300 has a yield strength of 310 MPa (45 ksi) and a tensile strength of 600 MPa (87 ksi) — stronger than 64% of copper alloy grades. Elongation at break is 22% and the elastic modulus is 103 GPa (14.9 Msi).
Thermal6
C67300 is rated for continuous service to 200°C (392 °F). It conducts heat at 60 W/m·K (34.7 BTU/hr·ft·°F), worse than 59% of copper alloy grades. Thermal expansion is 20.3 µm/m·K (11.3 µin/in·°F).
Electrical3
C67300 conducts electricity at 12 % IACS, worse than 62% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is good (60/100), worse than 68% of copper alloy grades.
Sustainability4
Producing a kilogram of C67300 takes about 52 MJ of energy and emits 3.3 kg of CO₂ — less than 87% of copper alloy grades. Typical recycled content is 45%.
Manufacturability7
C67300's machinability is very good (75/100, better than 80% of copper alloy grades); weldability poor (20/100); 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. C67300 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with C67300
Is C67300 easy to machine?
Free-machining behaviour thanks to lead and the β phase — sharp positive-rake carbide or HSS tools, high speeds, light feeds, short chips; expect ~75 % of C36000 rates.
Can C67300 be welded?
Fusion welding not recommended (lead cracking, zinc fume); join by brazing, silver soldering or mechanical fastening, with good ventilation.
Can C67300 be formed, bent or molded?
Excellent hot workability at 650–750 °C (extrusion, hot forging); cold bending is limited — anneal or design for hot-formed shapes.
C67300 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 |
|---|---|---|
| Cu | 58 – 63 | 60.5 |
| Mn | 2 – 3.5 | 2.7 |
| Al | 0.25 – 3 | 1 |
| Si | 0.5 – 1.5 | 0.9 |
| Pbadded for machinability | 0.4 – 3 | 1 |
| Fe | ≤ 0.5 | 0.2 |
| Sn | ≤ 0.3 | |
| Ni | ≤ 0.25 | |
| Znremainder, nominally ~32 % | balance |
What surface finishes work on C67300?
Polishes to a bright gold tone; accepts nickel, chrome or tin plating and chemical/black-oxide colouring — no anodising; use clear lacquer to prevent 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 C67300 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- B138
How much does C67300 cost?
C67300 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.
C67300 — frequently asked
What is C67300 used for?
C67300 is typically used for marine propeller hubs, gears, valve stems and heavy-duty fittings. In short: free-machining manganese bronze; 600 MPa tensile bar; hot-forging grade.
What is the yield strength of C67300?
C67300 has a typical yield strength of 310 MPa (45 ksi) and a tensile strength of 600 MPa (87 ksi) — stronger than 64% of copper alloy grades. Strength varies by condition: see the 5 listed tempers.
Is C67300 easy to machine?
Yes — machinability is rated very good (75/100, better than 80% of copper alloy grades). Free-machining behaviour thanks to lead and the β phase — sharp positive-rake carbide or HSS tools, high speeds, light feeds, short chips; expect ~75 % of C36000 rates.
Can C67300 be welded?
Not readily — weldability is rated poor (20/100). Fusion welding not recommended (lead cracking, zinc fume); join by brazing, silver soldering or mechanical fastening, with good ventilation.
What surface finishes work on C67300?
Polishes to a bright gold tone; accepts nickel, chrome or tin plating and chemical/black-oxide colouring — no anodising; use clear lacquer to prevent tarnish.
Can C67300 be formed, bent or molded?
Excellent hot workability at 650–750 °C (extrusion, hot forging); cold bending is limited — anneal or design for hot-formed shapes.
What is the maximum service temperature of C67300?
C67300 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 C67300-M30 and C67300-H04?
M30 is the default condition — standard stocked condition for rod, bar and shapes; best combination of strength, ductility and machinability. H04: maximum-strength drawn bar for heavily loaded pins, wear parts and fasteners; very limited ductility. Yield strength is 310 MPa in M30 versus 480 MPa in H04.
How much does C67300 cost?
C67300 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 B138 / B138M — Manganese Bronze Rod, Bar and Shapes — ASTM International (2019)
- ASTM B283 — Copper and Copper-Alloy Die Forgings (Hot-Pressed) — ASTM International (2020)
- CDA Standard Designation & Alloy Property Datasheets (UNS C67300) — Copper Development Association (2023)
- 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; 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.