Copper Alloy C85700
UNS C85700 · ASTM B584
C85700 is a high-strength leaded yellow (manganese) brass casting alloy to ASTM B584, in the C83000–C89999 cast brass family, using higher zinc content for strength beyond red and semi-red brasses.
Reference datasheet — C85700 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 M01 condition
C85700 tempers and conditions
C85700 is supplied in 4 conditions, soft to hard. M01 is the default FabDigit quotes; the values on this page are for it.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
M01Default As sand cast | Standard stocked condition: sand-cast valve bodies, fittings and hardware to ASTM B584. | 140 | 380 | 18 | 75 HB | 22 % IACS |
As pressure die cast | Use for near-net-shape decorative or intricate parts where machining allowance must be minimal. | 145 | 380 | 16 | 78 HB | 22 % IACS |
As centrifugally cast | Choose for cylindrical bushings/sleeves needing dense, porosity-free walls. | 160 | 400 | 16 | 80 HB | 22 % IACS |
As plaster cast | Pick for higher strength and better soundness in repetitive small parts (gear blanks, bushings, fittings). | 170 | 415 | 15 | 85 HB | 22 % IACS |
What is C85700?
C85700 is a high-strength leaded yellow (manganese) brass casting alloy to ASTM B584, in the C83000–C89999 cast brass family, using higher zinc content for strength beyond red and semi-red brasses. It is specified for cast gears, bushings and marine hardware, with typical values of 380 MPa tensile, 140 MPa yield, 18 % elongation, 75 HB, 84 W/m·K and 22 % IACS. Ductility is lower than red brass, fusion welding is impractical, the high zinc content makes it susceptible to dezincification, and service is limited to about 200 °C. C85700 has a density of 8.41 g/cm³ (0.304 lb/in³), lighter than 72% of copper alloy grades. It melts at 875°C (1,607 °F). C85700 has a yield strength of 140 MPa (20.3 ksi) and a tensile strength of 380 MPa (55.1 ksi) — weaker than 74% of copper alloy grades. Elongation at break is 18% and the elastic modulus is 100 GPa (14.5 Msi).
What is C85700 used for?
- gears
- bushings
- marine hardware
Advantages
- Easy to machine — 80/100, better than 86% of copper alloy grades
Limitations
- Needs corrosion protection — 45/100, worse than 98% of copper alloy grades
- Difficult to weld — 20/100, worse than 88% of copper alloy grades
- Low stiffness — 100 GPa (14.5 Msi), worse than 82% of copper alloy grades
C85700 properties
Typical room-temperature values for C85700-M01; bars are the position among copper alloy grades.
Physical3
C85700 has a density of 8.41 g/cm³ (0.304 lb/in³), lighter than 72% of copper alloy grades. It melts at 875°C (1,607 °F).
Mechanical11
C85700 has a yield strength of 140 MPa (20.3 ksi) and a tensile strength of 380 MPa (55.1 ksi) — weaker than 74% of copper alloy grades. Elongation at break is 18% and the elastic modulus is 100 GPa (14.5 Msi).
Thermal6
C85700 is rated for continuous service to 200°C (392 °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 21.6 µm/m·K (12 µin/in·°F).
Electrical3
C85700 conducts electricity at 22 % IACS, better than 55% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is fair (45/100), worse than 98% of copper alloy grades.
Sustainability4
Producing a kilogram of C85700 takes about 60 MJ of energy and emits 4 kg of CO₂ — more than 69% of copper alloy grades. Typical recycled content is 90%.
Manufacturability6
C85700's machinability is very good (80/100, better than 86% of copper alloy grades); weldability poor (20/100).
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. C85700 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with C85700
Is C85700 easy to machine?
Very free-cutting (≈80 % of C36000): use positive-rake, sharp tools, high speed, light feeds; chips break cleanly with lead present.
Can C85700 be welded?
Poor for fusion welding — zinc fume and lead cause porosity/hot cracking; repair by braze or silver-solder with flux and adequate fume extraction.
Can C85700 be formed, bent or molded?
A casting alloy only: good fluidity for sand, permanent-mold, centrifugal and investment casting; use generous risers on heavy sections and avoid cold working.
C85700 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 |
|---|---|---|
| CuASTM B584 C85700 | 58 – 64 | 61 |
| Sn | 0.5 – 1.5 | 1 |
| Pbfree-machining addition; not for lead-free potable water | 0.8 – 1.5 | 1.1 |
| Fe | ≤ 0.7 | |
| Al | ≤ 0.8 | |
| Nimax, incl. Co | ≤ 1 | |
| Mn | ≤ 0.25 | |
| Sb | ≤ 0.25 | |
| Zn | ≥ 32 (balance) |
What surface finishes work on C85700?
Buffs to a bright yellow finish; readily nickel/chrome plated or lacquered — no anodizing, and benzotriazole/lacquer helps prevent tarnish and dezincification.
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 C85700 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- B584
How much does C85700 cost?
C85700 is a premium-cost copper alloy ($$$), cheaper than about 51% 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.
C85700 — frequently asked
What is C85700 used for?
C85700 is typically used for gears, bushings and marine hardware. In short: high-strength yellow brass; stronger than red brass; dezincification-prone in service.
What is the yield strength of C85700?
C85700 has a typical yield strength of 140 MPa (20.3 ksi) and a tensile strength of 380 MPa (55.1 ksi) — weaker than 74% of copper alloy grades. Strength varies by condition: see the 4 listed tempers.
Is C85700 easy to machine?
Yes — machinability is rated very good (80/100, better than 86% of copper alloy grades). Very free-cutting (≈80 % of C36000): use positive-rake, sharp tools, high speed, light feeds; chips break cleanly with lead present.
Can C85700 be welded?
Not readily — weldability is rated poor (20/100). Poor for fusion welding — zinc fume and lead cause porosity/hot cracking; repair by braze or silver-solder with flux and adequate fume extraction.
What surface finishes work on C85700?
Buffs to a bright yellow finish; readily nickel/chrome plated or lacquered — no anodizing, and benzotriazole/lacquer helps prevent tarnish and dezincification.
Can C85700 be formed, bent or molded?
A casting alloy only: good fluidity for sand, permanent-mold, centrifugal and investment casting; use generous risers on heavy sections and avoid cold working.
What is the maximum service temperature of C85700?
C85700 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 C85700-M01 and C85700-M05?
M01 is the default condition — standard stocked condition: sand-cast valve bodies, fittings and hardware to ASTM B584. M05: pick for higher strength and better soundness in repetitive small parts (gear blanks, bushings, fittings). Yield strength is 140 MPa in M01 versus 170 MPa in M05.
How much does C85700 cost?
C85700 is a premium-cost copper alloy ($$$), cheaper than about 51% 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 B584 — Copper Alloy Sand Castings for General Applications — ASTM International (2022)
- CDA Alloy Datasheet C85700 (copper.org) — Copper Development Association (2023)
- ASM Handbook Vol. 2 — Properties of Nonferrous Alloys (Cast Copper 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.