Copper Alloy C86700
UNS C86700
C86700 is a leaded high-strength manganese bronze casting alloy that keeps most of the strength of the unleaded manganese bronzes while cutting far more freely.
Reference datasheet — C86700 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
C86700 tempers and conditions
C86700 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 as-cast sand-mould condition for gears, housings and marine hardware per ASTM B584. | 310 | 620 | 18 | 170 HB | 11 % IACS |
As continuous cast | Continuous-cast bar and tube stock for machined bushings and gear blanks — most uniform structure and best machined finish. | 330 | 650 | 18 | 175 HB | 11 % IACS |
As centrifugally cast | Choose for bushings, sleeves and worm-gear rims needing a dense, porosity-free wall and slightly higher strength. | 340 | 660 | 18 | 180 HB | 11 % IACS |
As pressure die cast | Use for medium-volume small parts where the faster chill gives finer grain, better surface and higher hardness. | 345 | 655 | 16 | 180 HB | 11 % IACS |
What is C86700?
C86700 is a leaded high-strength manganese bronze casting alloy that keeps most of the strength of the unleaded manganese bronzes while cutting far more freely. It is poured in sand, permanent-mould, centrifugal and continuous moulds for gears, bushings and marine fittings that require extensive machining: 620 MPa tensile, 310 MPa yield, 18% elongation, 170 HB, 200 °C maximum service temperature. Lead rules out fusion welding and reduces ductility relative to C86200, and dezincification limits stagnant seawater exposure; C86400 is the lower-strength, easier-machining option. C86700 has a density of 8.3 g/cm³ (0.3 lb/in³), lighter than 80% of copper alloy grades. It melts at 862°C (1,584 °F). C86700 has a yield strength of 310 MPa (45 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 64% of copper alloy grades. Elongation at break is 18% and the elastic modulus is 103 GPa (14.9 Msi).
What is C86700 used for?
- Gears
- Bushings
- Marine fittings
- Valve parts
Limitations
- Needs corrosion protection — 52/100, worse than 93% of copper alloy grades
- Poor heat conductor — 36 W/m·K (20.8 BTU/hr·ft·°F), worse than 86% of copper alloy grades
- Limited formability — 15/100, worse than 79% of copper alloy grades
- Difficult to weld — 25/100, worse than 78% of copper alloy grades
C86700 properties
Typical room-temperature values for C86700-M01; bars are the position among copper alloy grades.
Physical3
C86700 has a density of 8.3 g/cm³ (0.3 lb/in³), lighter than 80% of copper alloy grades. It melts at 862°C (1,584 °F).
Mechanical15
C86700 has a yield strength of 310 MPa (45 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 64% of copper alloy grades. Elongation at break is 18% and the elastic modulus is 103 GPa (14.9 Msi).
Thermal6
C86700 is rated for continuous service to 200°C (392 °F). It conducts heat at 36 W/m·K (20.8 BTU/hr·ft·°F), worse than 86% of copper alloy grades. Thermal expansion is 20.3 µm/m·K (11.3 µin/in·°F).
Electrical3
C86700 conducts electricity at 11 % IACS, worse than 68% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is fair (52/100), worse than 93% of copper alloy grades.
Sustainability4
Producing a kilogram of C86700 takes about 45 MJ of energy and emits 3.4 kg of CO₂ — less than 97% of copper alloy grades. Typical recycled content is 75%.
Manufacturability8
C86700's machinability is good (60/100, better than 74% of copper alloy grades); weldability poor (25/100); formability poor (15/100).
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. C86700 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with C86700
Is C86700 easy to machine?
Lead addition makes it the easiest of the high-strength manganese bronzes to cut (~60% of free-cutting brass); use sharp positive-rake carbide, high speed, light feed and copious coolant.
Can C86700 be welded?
Fusion welding is not recommended — lead causes hot cracking and zinc fumes; repair by brazing or mechanical fastening and use ventilation for any hot work.
Can C86700 be formed, bent or molded?
Sand, permanent-mould, centrifugal and continuous casting all work well; feed heavily with chills and risers due to the short freezing range and use a low-turbulence gating to avoid oxide films.
C86700 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 | 55 – 60 | 58 |
| Sn | ≤ 1.5 | 0.8 |
| Pbadded for machinability | 0.5 – 1.5 | 1 |
| Fe | 1 – 3 | 2 |
| Al | 1 – 3 | 2 |
| Mn | 0.1 – 3.5 | 1 |
| Niincl. Co | ≤ 1 | |
| Zntypically ~34% | balance |
What surface finishes work on C86700?
Takes a good mechanical polish and accepts nickel, chrome or tin electroplating; no anodizing — for marine service consider cathodic protection or coatings to limit 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).
How much does C86700 cost?
C86700 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.
C86700 — frequently asked
What is C86700 used for?
C86700 is typically used for gears, bushings, marine fittings and valve parts. In short: free-machining high-strength bronze; strength with low machining cost.
What is the yield strength of C86700?
C86700 has a typical yield strength of 310 MPa (45 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 64% of copper alloy grades. Strength varies by condition: see the 4 listed tempers.
Is C86700 easy to machine?
Reasonably — machinability is rated good (60/100, better than 74% of copper alloy grades). Lead addition makes it the easiest of the high-strength manganese bronzes to cut (~60% of free-cutting brass); use sharp positive-rake carbide, high speed, light feed and copious coolant.
Can C86700 be welded?
Not readily — weldability is rated poor (25/100). Fusion welding is not recommended — lead causes hot cracking and zinc fumes; repair by brazing or mechanical fastening and use ventilation for any hot work.
What surface finishes work on C86700?
Takes a good mechanical polish and accepts nickel, chrome or tin electroplating; no anodizing — for marine service consider cathodic protection or coatings to limit dezincification.
Can C86700 be formed, bent or molded?
Sand, permanent-mould, centrifugal and continuous casting all work well; feed heavily with chills and risers due to the short freezing range and use a low-turbulence gating to avoid oxide films.
What is the maximum service temperature of C86700?
C86700 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 C86700-M01 and C86700-M04?
M01 is the default condition — standard as-cast sand-mould condition for gears, housings and marine hardware per ASTM B584. M04: use for medium-volume small parts where the faster chill gives finer grain, better surface and higher hardness. Yield strength is 310 MPa in M01 versus 345 MPa in M04.
How much does C86700 cost?
C86700 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 B584 Standard Specification for Copper Alloy Sand Castings for General Applications — ASTM International (2022)
- ASTM B505/B505M Copper Alloy Continuous Castings — ASTM International (2018)
- CDA Alloy Datasheet C86700 (leaded manganese bronze) — Copper Development Association (2023)
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- ASM Handbook Vol.13B — Corrosion: Materials — 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.