Copper Alloy C99400
UNS C99400 · ASTM B584
C99400 is a special-composition cast copper-zinc-nickel-aluminium alloy under ASTM B584, available in F, M01, M05 and heat-treated (HT) conditions.
Reference datasheet — C99400 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 F condition
C99400 tempers and conditions
C99400 is supplied in 4 conditions, soft to hard. F 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 |
|---|---|---|---|---|---|---|
FDefault As fabricated | Default stocked/produced condition: good ductility and toughness for general marine and industrial castings. | 205 | 415 | 20 | 125 HB | 8 % IACS |
As sand cast | Standard as-sand-cast condition of C99400 nickel-manganese-aluminium bronze-brass, combining ~415 MPa strength with good ductility, seawater corrosion resistance and easy machining. | 221 | 448 | 22 | 140 HB | 8 % IACS |
As plaster cast | Choose for thinner, faster-solidified sections: finer grain gives ~5–10 % higher strength and hardness than sand cast. | 230 | 450 | 18 | 135 HB | 8 % IACS |
Solution treated and precipitation (age) hardened | Choose when maximum strength, wear resistance and hardness are needed (gears, bushings, high-load valve parts) and lower ductility is acceptable. | 380 | 545 | 12 | 180 HB | 10 % IACS |
What is C99400?
C99400 is a special-composition cast copper-zinc-nickel-aluminium alloy under ASTM B584, available in F, M01, M05 and heat-treated (HT) conditions. It is specified for marine and industrial hardware needing corrosion resistance (rated 72) with 415 MPa tensile strength, 205 MPa yield, 20% elongation, 125 HB (72 HRB), 117 GPa modulus, 42 W/m·K and service to 250 °C. Conductivity is low at 8% IACS, machinability is rated 62 because of hard silicide particles, and the aluminium content makes welding hot-short and oxide-prone. Choose a cast silicon brass such as C87900 when corrosion demands are lower. C99400 has a density of 8 g/cm³ (0.289 lb/in³), lighter than 87% of copper alloy grades. It melts at 996°C (1,825 °F). C99400 has a yield strength of 205 MPa (29.7 ksi) and a tensile strength of 415 MPa (60.2 ksi) — weaker than 53% of copper alloy grades. Elongation at break is 20% and the elastic modulus is 117 GPa (17 Msi).
What is C99400 used for?
- marine hardware
- pump components
- valve bodies
- industrial fittings
Advantages
- Good corrosion resistance — 72/100, better than 84% of copper alloy grades
- Easy to machine — 62/100, better than 75% of copper alloy grades
Limitations
- Limited formability — 10/100, worse than 89% of copper alloy grades
- Low electrical conductivity — 8 % IACS, worse than 81% of copper alloy grades
- Poor heat conductor — 42 W/m·K (24.3 BTU/hr·ft·°F), worse than 80% of copper alloy grades
C99400 properties
Typical room-temperature values for C99400-F; bars are the position among copper alloy grades.
Physical3
C99400 has a density of 8 g/cm³ (0.289 lb/in³), lighter than 87% of copper alloy grades. It melts at 996°C (1,825 °F).
Mechanical13
C99400 has a yield strength of 205 MPa (29.7 ksi) and a tensile strength of 415 MPa (60.2 ksi) — weaker than 53% of copper alloy grades. Elongation at break is 20% and the elastic modulus is 117 GPa (17 Msi).
Thermal6
C99400 is rated for continuous service to 250°C (482 °F). It conducts heat at 42 W/m·K (24.3 BTU/hr·ft·°F), worse than 80% of copper alloy grades. Thermal expansion is 16.2 µm/m·K (9 µin/in·°F).
Electrical3
C99400 conducts electricity at 8 % IACS, worse than 81% 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 C99400 takes about 48 MJ of energy and emits 3.4 kg of CO₂ — less than 92% of copper alloy grades. Typical recycled content is 70%.
Manufacturability7
C99400's machinability is good (62/100, better than 75% of copper alloy grades); weldability fair (40/100); formability not recommended (10/100).
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. C99400 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with C99400
Is C99400 easy to machine?
Machines like a medium-hard bronze (~80 % of free-cutting brass): use sharp carbide tools, positive rake, moderate speeds and flood coolant; hard silicide particles increase tool wear, and the aged HT condition cuts noticeably slower.
Can C99400 be welded?
GTAW/GMAW possible with matched or silicon-bronze filler and 150–250 °C preheat, but the aluminium content forms a tenacious oxide and the alloy is hot-short — clean thoroughly, avoid heavy restraint, and re-age after welding of HT parts.
Can C99400 be formed, bent or molded?
Foundry alloy only — good fluidity for sand, permanent-mold and centrifugal casting; feed heavy sections with risers and use degassing to avoid gas porosity; no cold forming.
C99400 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 |
|---|---|---|
| NiNi + Co | 1 – 3.5 | 2.2 |
| Fe | 1 – 3 | 1.8 |
| Al | 0.5 – 2 | 1.2 |
| Siwith Ni forms age-hardening silicides | 0.5 – 2 | 1.2 |
| Zn | 0.5 – 2 | 1.2 |
| Mn | ≤ 0.5 | 0.3 |
| Pbimpurity limit | ≤ 0.25 | |
| Cu | balance |
What surface finishes work on C99400?
Takes a bright white polish and buffs well; not anodisable — protect with tin, nickel or chrome plating, chemical passivation or clear lacquer; abrasive blasting removes casting skin before plating.
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 C99400 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- B584
How much does C99400 cost?
C99400 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.
C99400 — frequently asked
What is C99400 used for?
C99400 is typically used for marine hardware, pump components, valve bodies and industrial fittings. In short: most corrosion-resistant cast brass; heat-treatable to higher hardness; slowest machining of the family.
What is the yield strength of C99400?
C99400 has a typical yield strength of 205 MPa (29.7 ksi) and a tensile strength of 415 MPa (60.2 ksi) — weaker than 53% of copper alloy grades. Strength varies by condition: see the 4 listed tempers.
Is C99400 easy to machine?
Reasonably — machinability is rated good (62/100, better than 75% of copper alloy grades). Machines like a medium-hard bronze (~80 % of free-cutting brass): use sharp carbide tools, positive rake, moderate speeds and flood coolant; hard silicide particles increase tool wear, and the aged HT condition cuts noticeably slower.
Can C99400 be welded?
With care — weldability is rated fair (40/100). GTAW/GMAW possible with matched or silicon-bronze filler and 150–250 °C preheat, but the aluminium content forms a tenacious oxide and the alloy is hot-short — clean thoroughly, avoid heavy restraint, and re-age after welding of HT parts.
What surface finishes work on C99400?
Takes a bright white polish and buffs well; not anodisable — protect with tin, nickel or chrome plating, chemical passivation or clear lacquer; abrasive blasting removes casting skin before plating.
Can C99400 be formed, bent or molded?
Foundry alloy only — good fluidity for sand, permanent-mold and centrifugal casting; feed heavy sections with risers and use degassing to avoid gas porosity; no cold forming.
What is the maximum service temperature of C99400?
C99400 is rated for continuous use to about 250°C (482 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between C99400-F and C99400-HT?
F is the default condition — default stocked/produced condition: good ductility and toughness for general marine and industrial castings. HT: choose when maximum strength, wear resistance and hardness are needed (gears, bushings, high-load valve parts) and lower ductility is acceptable. Yield strength is 205 MPa in F versus 380 MPa in HT.
How much does C99400 cost?
C99400 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)
- CDA Alloy Database — C99400 composition and properties — Copper Development Association (copper.org) (2023)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials — ASM International (1990)
- ASM Specialty Handbook: Copper and Copper Alloys — ASM International (2001)
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.