Copper Alloy C97800
UNS C97800
C97800 is the highest-nickel, highest-strength grade in the leaded nickel silver casting series, combining a Cu-Ni-Zn-Sn matrix with lead for machinability.
Reference datasheet — C97800 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
C97800 tempers and conditions
C97800 is supplied in 5 conditions, soft to hard. M01 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 |
|---|---|---|---|---|---|---|
M01Default As sand cast | Standard stocked/produced condition for general castings to ASTM B584 — gears, valve parts, ornamental hardware. | 225 | 400 | 15 | 130 HB | 4.5 % IACS |
As investment cast | Choose for intricate ornamental or near-net-shape parts where machining allowance must be minimal. | 225 | 400 | 13 | 130 HB | 4.5 % IACS |
As plaster cast | For medium-volume runs of small hardware needing better surface finish and dimensional repeatability than sand casting. | 235 | 415 | 14 | 133 HB | 4.5 % IACS |
As centrifugally cast | Pick for rings, bushings and worm-gear blanks needing sounder, finer-grained metal than sand casting. | 240 | 425 | 15 | 135 HB | 4.5 % IACS |
As continuous cast | Best choice for bar and tube stock machined into bushings and gear blanks; densest, most uniform structure (ASTM B505). | 250 | 435 | 15 | 140 HB | 4.5 % IACS |
What is C97800?
C97800 is the highest-nickel, highest-strength grade in the leaded nickel silver casting series, combining a Cu-Ni-Zn-Sn matrix with lead for machinability. Engineers specify it for gears, bearings and ornamental hardware that need strength together with corrosion resistance, in sand, permanent-mould, investment and continuous castings at 225 MPa yield, 400 MPa tensile, 15 % elongation and 130 HB. Elongation and electrical conductivity (4.5 % IACS) are lower than in C97600, and the lead plus hot-short Cu-Ni-Sn structure means it cannot be fusion welded. Choose C97600 when free machining and food contact matter more than strength. C97800 has a density of 8.8 g/cm³ (0.318 lb/in³), heavier than 58% of copper alloy grades. It melts at 1,065°C (1,949 °F). C97800 has a yield strength of 225 MPa (32.6 ksi) and a tensile strength of 400 MPa (58 ksi) — stronger than 50% of copper alloy grades. Elongation at break is 15% and the elastic modulus is 124 GPa (18 Msi).
What is C97800 used for?
- gears
- bearings and bushings
- marine hardware
- ornamental fittings
Advantages
- Polishes to a fine finish — 85/100, better than 92% of copper alloy grades
- Good corrosion resistance — 72/100, better than 84% of copper alloy grades
- High service temperature — 260°C (500 °F), better than 75% of copper alloy grades
Limitations
- Poor heat conductor — 25 W/m·K (14.4 BTU/hr·ft·°F), worse than 98% of copper alloy grades
- Low electrical conductivity — 4.5 % IACS, worse than 98% of copper alloy grades
- High embodied carbon — 5.6 kg CO₂/kg, worse than 91% 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
C97800 properties
Typical room-temperature values for C97800-M01; bars are the position among copper alloy grades.
Physical3
C97800 has a density of 8.8 g/cm³ (0.318 lb/in³), heavier than 58% of copper alloy grades. It melts at 1,065°C (1,949 °F).
Mechanical14
C97800 has a yield strength of 225 MPa (32.6 ksi) and a tensile strength of 400 MPa (58 ksi) — stronger than 50% of copper alloy grades. Elongation at break is 15% and the elastic modulus is 124 GPa (18 Msi).
Thermal6
C97800 is rated for continuous service to 260°C (500 °F). It conducts heat at 25 W/m·K (14.4 BTU/hr·ft·°F), worse than 98% of copper alloy grades. Thermal expansion is 16.2 µm/m·K (9 µin/in·°F).
Electrical3
C97800 conducts electricity at 4.5 % IACS, worse than 98% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is very good (72/100), better than 84% of copper alloy grades.
Sustainability4
Producing a kilogram of C97800 takes about 78 MJ of energy and emits 5.6 kg of CO₂ — more than 90% of copper alloy grades. Typical recycled content is 40%.
Manufacturability8
C97800's machinability is good (58/100, better than 73% 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. C97800 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with C97800
Is C97800 easy to machine?
Machines to a clean silvery finish at ~60% of free-cutting brass; the high-nickel matrix work-hardens, so use sharp carbide, positive rake, moderate speed with steady feed and soluble-oil coolant.
Can C97800 be welded?
Fusion welding is not recommended because of the lead content and hot-short Cu-Ni-Sn structure; join by silver brazing or soft soldering, and preheat/stress-relieve repairs.
Can C97800 be formed, bent or molded?
Foundry alloy only — pour hot (~1200–1250 °C) with good risering and directional solidification to avoid tin/lead interdendritic shrinkage; not intended for cold forming.
C97800 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 |
|---|---|---|
| Niincludes Co | 24 – 27 | 25.5 |
| Sn | 4 – 5.5 | 4.7 |
| Pbmachinability/pressure tightness | 1 – 2.5 | 1.8 |
| Zn | 1 – 4 | 2.5 |
| Fe | ≤ 1.5 | |
| Mn | ≤ 1.5 | |
| Sb | ≤ 0.15 | |
| Si | ≤ 0.15 | |
| S | ≤ 0.08 | |
| P | ≤ 0.05 | |
| Al | ≤ 0.01 | |
| Cu | ≥ 64 (balance) |
What surface finishes work on C97800?
Takes a high natural silver-white polish and accepts nickel or chromium plating readily; anodizing is not applicable, and lacquer or clear coat prevents slow tarnish outdoors.
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 C97800 cost?
C97800 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.
C97800 — frequently asked
What is C97800 used for?
C97800 is typically used for gears, bearings and bushings, marine hardware and ornamental fittings. In short: strongest leaded nickel silver; gear and bearing casting grade; bright silver-white polish.
What is the yield strength of C97800?
C97800 has a typical yield strength of 225 MPa (32.6 ksi) and a tensile strength of 400 MPa (58 ksi) — stronger than 50% of copper alloy grades. Strength varies by condition: see the 5 listed tempers.
Is C97800 easy to machine?
Reasonably — machinability is rated good (58/100, better than 73% of copper alloy grades). Machines to a clean silvery finish at ~60% of free-cutting brass; the high-nickel matrix work-hardens, so use sharp carbide, positive rake, moderate speed with steady feed and soluble-oil coolant.
Can C97800 be welded?
Not readily — weldability is rated poor (25/100). Fusion welding is not recommended because of the lead content and hot-short Cu-Ni-Sn structure; join by silver brazing or soft soldering, and preheat/stress-relieve repairs.
What surface finishes work on C97800?
Takes a high natural silver-white polish and accepts nickel or chromium plating readily; anodizing is not applicable, and lacquer or clear coat prevents slow tarnish outdoors.
Can C97800 be formed, bent or molded?
Foundry alloy only — pour hot (~1200–1250 °C) with good risering and directional solidification to avoid tin/lead interdendritic shrinkage; not intended for cold forming.
What is the maximum service temperature of C97800?
C97800 is rated for continuous use to about 260°C (500 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between C97800-M01 and C97800-M07?
M01 is the default condition — standard stocked/produced condition for general castings to ASTM B584 — gears, valve parts, ornamental hardware. M07: best choice for bar and tube stock machined into bushings and gear blanks; densest, most uniform structure (ASTM B505). Yield strength is 225 MPa in M01 versus 250 MPa in M07.
How much does C97800 cost?
C97800 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 C97800 (25% leaded nickel silver) — Copper Development Association (2023)
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials — 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.