Copper Alloy C85700-M05
Finish state
UNS C85700 · ASTM B584
M05 = as plaster cast
Pick for higher strength and better soundness in repetitive small parts (gear blanks, bushings, fittings).
Values for the M05 condition
Other C85700 tempers and conditions
C85700 is listed in 4 conditions; see the grade overview at C85700.
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 |
M05This page 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-M05?
C85700-M05 is C85700 supplied in the M05 condition — pick for higher strength and better soundness in repetitive small parts (gear blanks, bushings, fittings). C85700-M05 has a yield strength of 170 MPa (24.7 ksi) and a tensile strength of 415 MPa (60.2 ksi) — weaker than 62% of copper alloy grades. Elongation at break is 15% and the elastic modulus is 100 GPa (14.5 Msi). C85700-M05 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). M01 is the default condition FabDigit quotes; M05 is available on request or by drawing note.
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-M05 properties
Typical room-temperature values for C85700-M05; 20 are specific to this condition. Other listed values are C85700 reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
C85700-M05 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-M05 has a yield strength of 170 MPa (24.7 ksi) and a tensile strength of 415 MPa (60.2 ksi) — weaker than 62% of copper alloy grades. Elongation at break is 15% and the elastic modulus is 100 GPa (14.5 Msi).
Thermal6
C85700-M05 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-M05 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-M05 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-M05's machinability is very good (80/100, better than 86% of copper alloy grades); weldability poor (20/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with C85700-M05
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.
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.
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) | — |
C85700-M05 — frequently asked
What is C85700-M05 used for?
C85700-M05 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-M05?
C85700-M05 has a typical yield strength of 170 MPa (24.7 ksi) and a tensile strength of 415 MPa (60.2 ksi) — weaker than 62% of copper alloy grades. Strength varies by condition: see the 4 listed tempers.
Is C85700-M05 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-M05 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-M05?
Buffs to a bright yellow finish; readily nickel/chrome plated or lacquered — no anodizing, and benzotriazole/lacquer helps prevent tarnish and dezincification.
Can C85700-M05 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-M05?
C85700-M05 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.
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. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.