Copper Alloy C66700
UNS C66700
C66700 is a manganese-bearing wrought brass with higher strength and hardness than plain brass, supplied as strip in OS050 and OS025 annealed tempers and H01 through H10 cold-rolled tempers.
Reference datasheet — C66700 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 H02 condition
C66700 tempers and conditions
C66700 is supplied in 9 conditions, soft to hard. H02 is the default FabDigit quotes; the values on this page are for it.
Compare all 9 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed to 0.050 mm grain size | Softest commercial temper for deep drawing and severe bending of strip. | 110 | 350 | 60 | 65 HB | — |
Annealed to 0.025 mm grain size | Fine-grain annealed strip: smoother formed surfaces and slightly higher strength than OS050. | 140 | 375 | 52 | 80 HB | — |
Quarter hard | Light cold work for parts needing moderate stiffness with generous bending. | 275 | 420 | 40 | 105 HB | — |
H02Default Half hard | Most-stocked balance of strength and formability for stamped hardware and fasteners. | 380 | 470 | 25 | 120 HB | — |
Three-quarter hard | Higher strength with limited bend capability, for load-carrying stampings. | 430 | 515 | 16 | 140 HB | — |
Full hard | Standard hard temper for flat springs, clips and wear-resistant stampings with only gentle forming. | 470 | 550 | 10 | 155 HB | — |
Extra hard | For high-stiffness contacts and wear parts where forming is limited to flat blanking. | 540 | 620 | 6 | 175 HB | — |
Spring hard | Spring temper strip/wire for high elastic-limit contacts and washers. | 580 | 660 | 4 | 190 HB | — |
Extra spring hard | Maximum cold-worked strength; brittle to bending, used for flat springs and thin high-load contacts. | 615 | 690 | 3 | 200 HB | — |
What is C66700?
C66700 is a manganese-bearing wrought brass with higher strength and hardness than plain brass, supplied as strip in OS050 and OS025 annealed tempers and H01 through H10 cold-rolled tempers. It combines 380 MPa yield, 470 MPa tensile, 25 % elongation and 120 HB (68 HRB) with good deep-draw behaviour (formability score 66), which suits drawn fasteners, wear parts and structural hardware. It is unleaded and machines at roughly 30 % of free-cutting brass, is not anodizable, and cold-worked parts need stress relief to avoid season cracking. C66900 is the higher-strength manganese brass when 380 MPa yield is not enough. C66700 has a density of 8.41 g/cm³ (0.304 lb/in³), lighter than 72% of copper alloy grades. It melts at 915°C (1,679 °F). C66700 has a yield strength of 380 MPa (55.1 ksi) and a tensile strength of 470 MPa (68.2 ksi) — stronger than 77% of copper alloy grades. Elongation at break is 25% and the elastic modulus is 110 GPa (16 Msi).
What is C66700 used for?
- fasteners
- wear-resistant components
- structural hardware
Advantages
- Forms and bends easily — 66/100, better than 79% of copper alloy grades
- High strength — 380 MPa (55.1 ksi), better than 77% of copper alloy grades
Limitations
- Limited service temperature — 150°C (302 °F), worse than 96% of copper alloy grades
C66700 properties
Typical room-temperature values for C66700-H02; bars are the position among copper alloy grades.
Physical3
C66700 has a density of 8.41 g/cm³ (0.304 lb/in³), lighter than 72% of copper alloy grades. It melts at 915°C (1,679 °F).
Mechanical12
C66700 has a yield strength of 380 MPa (55.1 ksi) and a tensile strength of 470 MPa (68.2 ksi) — stronger than 77% of copper alloy grades. Elongation at break is 25% and the elastic modulus is 110 GPa (16 Msi).
Thermal6
C66700 is rated for continuous service to 150°C (302 °F). It conducts heat at 84 W/m·K (48.5 BTU/hr·ft·°F), better than 51% of copper alloy grades. Thermal expansion is 20 µm/m·K (11.1 µin/in·°F).
Electrical3
C66700 conducts electricity at 17 % IACS, better than 50% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is good (58/100), worse than 76% of copper alloy grades.
Sustainability4
Producing a kilogram of C66700 takes about 55 MJ of energy and emits 3.6 kg of CO₂ — less than 72% of copper alloy grades. Typical recycled content is 45%.
Manufacturability8
C66700's machinability is poor (32/100, worse than 57% of copper alloy grades); weldability fair (45/100); formability good (66/100).
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. C66700 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with C66700
Is C66700 easy to machine?
Machinability roughly 30 % of free-cutting brass — gummy chips; use sharp positive-rake carbide, high speed, light feeds and good lubrication.
Can C66700 be welded?
Resistance and GTAW welding are fair; zinc volatilises so use ventilation and low heat input, and prefer brazing or soldering for joints.
Can C66700 be formed, bent or molded?
Excellent deep-draw and bend behaviour in OS tempers; interstage anneal at 425–600 °C, and stress-relieve cold-worked parts near 260 °C to avoid season cracking.
C66700 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 | 68.5 – 71.5 | 70 |
| Mnsolid-solution strengthener | 0.8 – 1.5 | 1.1 |
| Fe | ≤ 0.1 | |
| Pb | ≤ 0.07 | |
| Zn | balance |
What surface finishes work on C66700?
Not anodisable; bright-dip, mechanically polish, or apply Ni/Cr, tin or clear lacquer — keep away from ammonia-based cleaners.
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).
How much does C66700 cost?
C66700 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.
C66700 — frequently asked
What is C66700 used for?
C66700 is typically used for fasteners, wear-resistant components and structural hardware. In short: manganese-strengthened drawing brass; 25 % elongation strip; stronger than cartridge brass.
What is the yield strength of C66700?
C66700 has a typical yield strength of 380 MPa (55.1 ksi) and a tensile strength of 470 MPa (68.2 ksi) — stronger than 77% of copper alloy grades. Strength varies by condition: see the 9 listed tempers.
Is C66700 easy to machine?
Not especially — machinability is rated poor (32/100, worse than 57% of copper alloy grades). Machinability roughly 30 % of free-cutting brass — gummy chips; use sharp positive-rake carbide, high speed, light feeds and good lubrication.
Can C66700 be welded?
With care — weldability is rated fair (45/100). Resistance and GTAW welding are fair; zinc volatilises so use ventilation and low heat input, and prefer brazing or soldering for joints.
What surface finishes work on C66700?
Not anodisable; bright-dip, mechanically polish, or apply Ni/Cr, tin or clear lacquer — keep away from ammonia-based cleaners.
Can C66700 be formed, bent or molded?
Excellent deep-draw and bend behaviour in OS tempers; interstage anneal at 425–600 °C, and stress-relieve cold-worked parts near 260 °C to avoid season cracking.
What is the maximum service temperature of C66700?
C66700 is rated for continuous use to about 150°C (302 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between C66700-H02 and C66700-OS050?
H02 is the default condition — most-stocked balance of strength and formability for stamped hardware and fasteners. OS050: softest commercial temper for deep drawing and severe bending of strip. Yield strength is 380 MPa in H02 versus 110 MPa in OS050.
How much does C66700 cost?
C66700 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
- CDA Alloy Data: C66700 Manganese Brass — Copper Development Association (copper.org) (2024)
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- ASTM B36/B36M — Brass Plate, Sheet, Strip and Rolled Bar — ASTM (2018)
- ASTM B601 — Temper Designations for Copper and Copper Alloys — ASTM (2019)
- ASM Handbook Vol.13B — Corrosion: Materials (copper alloys) — ASM International (2005)
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.