Copper Alloy C84400
UNS C84400 · ASTM B584
C84400 is a leaded semi-red brass casting alloy (about 81Cu-3Sn-7Pb-9Zn) supplied to ASTM B584 and B505 as sand, continuous and centrifugal castings.
Values for the As Cast condition
C84400 tempers and conditions
C84400 is supplied in 3 conditions, soft to hard. As Cast is the default FabDigit quotes; the values on this page are for it.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
As CastDefault sand cast, as-cast (M01) | Standard ASTM B584 sand-cast condition — the way virtually all C84400 valve bodies and fittings are supplied. | 110 | 234 | 26 | 55 HB | 16.4 % IACS |
ASTM B271 spun-cast rings and sleeves | Use for large-diameter rings, sleeves and pump wear parts where a dense, void-free wall is required. | 117 | 241 | 22 | 58 HB | 16.4 % IACS |
ASTM B505 continuous/permanent-mould cast bar and tube | Pick for machined bushings, bar stock and tube blanks — finer, denser structure gives slightly higher strength and hardness than sand cast. | 124 | 248 | 20 | 60 HB | 16.4 % IACS |
What is C84400?
C84400 is a leaded semi-red brass casting alloy (about 81Cu-3Sn-7Pb-9Zn) supplied to ASTM B584 and B505 as sand, continuous and centrifugal castings. The high lead content gives free-machining behaviour and good pressure tightness, making it a low-cost choice for low-pressure valve bodies, water meter housings, flanges, pipe fittings and general bushings, cheaper than higher-tin C83600. Limits are modest strength (234 MPa tensile, 110 MPa yield), dezincification risk (avoid ammonia-bearing media and high-velocity seawater) and the lead itself, so potable-water systems now use lead-free grades such as C89833 or C87850. C84400 has a density of 8.8 g/cm³ (0.318 lb/in³), heavier than 58% of copper alloy grades. It melts at 843°C (1,549 °F). C84400 has a yield strength of 110 MPa (16 ksi) and a tensile strength of 234 MPa (33.9 ksi) — weaker than 82% of copper alloy grades. Elongation at break is 26% and the elastic modulus is 95 GPa (13.8 Msi).
What is C84400 used for?
- Bushings
- Bearings
- Pump impellers
Advantages
- Easy to machine — 90/100, better than 98% of copper alloy grades
- Low embodied carbon — 3.2 kg CO₂/kg, better than 92% of copper alloy grades
Limitations
- Low stiffness — 95 GPa (13.8 Msi), worse than 93% of copper alloy grades
- Hard to polish — 60/100, worse than 92% of copper alloy grades
- Limited formability — 10/100, worse than 89% of copper alloy grades
- Difficult to weld — 20/100, worse than 88% of copper alloy grades
- Low strength — 110 MPa (16 ksi), worse than 82% of copper alloy grades
C84400 properties
Typical room-temperature values for C84400-As Cast; bars are the position among copper alloy grades.
Physical3
C84400 has a density of 8.8 g/cm³ (0.318 lb/in³), heavier than 58% of copper alloy grades. It melts at 843°C (1,549 °F).
Mechanical13
C84400 has a yield strength of 110 MPa (16 ksi) and a tensile strength of 234 MPa (33.9 ksi) — weaker than 82% of copper alloy grades. Elongation at break is 26% and the elastic modulus is 95 GPa (13.8 Msi).
Thermal6
C84400 is rated for continuous service to 200°C (392 °F). It conducts heat at 72 W/m·K (41.6 BTU/hr·ft·°F), worse than 52% of copper alloy grades. Thermal expansion is 18 µm/m·K (10 µin/in·°F).
Electrical3
C84400 conducts electricity at 16.4 % IACS, worse than 51% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is good (58/100), worse than 76% of copper alloy grades.
Sustainability4
Producing a kilogram of C84400 takes about 42 MJ of energy and emits 3.2 kg of CO₂ — less than 99% of copper alloy grades. Typical recycled content is 85%.
Manufacturability8
C84400's machinability is excellent (90/100, better than 98% of copper alloy grades); weldability poor (20/100); 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. C84400 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with C84400
Is C84400 easy to machine?
Excellent free-machining behaviour (≈90 % of C36000) — lead gives short chips; use sharp positive-rake tools, high speed, light feed and flood coolant, and observe lead-dust/OSHA controls.
Can C84400 be welded?
Poor fusion weldability because of lead volatilisation and hot cracking; join by soft soldering (excellent) or silver brazing (fair-good), and repair porosity with brazing rather than TIG.
Can C84400 be formed, bent or molded?
Casting-only alloy: excellent sand, permanent-mould and continuous-cast fluidity with good pressure tightness; not suited to cold forming or hot working.
Manufacturability
The process limits FabDigit applies to C84400. Every C84400 part is priced by an engineer; design inside these and the quote comes back without a redesign loop.
CNC machining
| Machinability | Better90 / 100 |
|---|---|
| ISO material group | N.5 |
| Cutting speed (rough / finish) | 180 / 220 m/min |
| Minimum wall | 0.8 mm |
| Minimum internal radius | 1 mm |
| Drill depth limit | 6× diameter |
| Best surface (machined / polished) | Ra 1.6 / — |
| Hardenable after machining | No |
C84400 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 C84400 | 78 – 82 | 81 |
| Sn | 2.3 – 3.5 | 3 |
| Pbnot for lead-free potable-water service | 6 – 8 | 7 |
| Fe | ≤ 0.4 | |
| Sb | ≤ 0.25 | |
| Niincl. Co | ≤ 1 | |
| S | ≤ 0.08 | |
| P | ≤ 0.02 | |
| Al | ≤ 0.01 | |
| Si | ≤ 0.01 | |
| Zn | ≥ 7 (balance) |
What surface finishes work on C84400?
Cannot be anodised; take mechanical polish, tin, nickel or chrome plating (tin plating common for water-service interiors), or chemical patina/lacquer for decorative parts.
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).
Passivation
Plating
Organic Coating
Equivalent designations
Standards and trade names that resolve to Copper Alloy C84400 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- B584
- Trade names
- Valve MetalAlloy 5A
- Also called
- Leaded Semi-Red Brass
How much does C84400 cost?
C84400 is a specialty-cost copper alloy ($$$$$), pricier than about 59% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
C84400 — frequently asked
What is C84400 used for?
C84400 is typically used for bushings, bearings and pump impellers. In short: acid-proof bronze.
What is the yield strength of C84400?
C84400 has a typical yield strength of 110 MPa (16 ksi) and a tensile strength of 234 MPa (33.9 ksi) — weaker than 82% of copper alloy grades. Strength varies by condition: see the 3 listed tempers.
Is C84400 easy to machine?
Yes — machinability is rated excellent (90/100, better than 98% of copper alloy grades). Excellent free-machining behaviour (≈90 % of C36000) — lead gives short chips; use sharp positive-rake tools, high speed, light feed and flood coolant, and observe lead-dust/OSHA controls.
Can C84400 be welded?
Not readily — weldability is rated poor (20/100). Poor fusion weldability because of lead volatilisation and hot cracking; join by soft soldering (excellent) or silver brazing (fair-good), and repair porosity with brazing rather than TIG.
What surface finishes work on C84400?
Cannot be anodised; take mechanical polish, tin, nickel or chrome plating (tin plating common for water-service interiors), or chemical patina/lacquer for decorative parts.
Can C84400 be formed, bent or molded?
Casting-only alloy: excellent sand, permanent-mould and continuous-cast fluidity with good pressure tightness; not suited to cold forming or hot working.
What is the maximum service temperature of C84400?
C84400 is rated for continuous use to about 200°C (392 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does C84400 cost?
C84400 is a specialty-cost copper alloy ($$$$$), pricier than about 59% 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.
Can FabDigit make parts in C84400?
Yes — C84400 is available for CNC machining; every part is priced by an engineer rather than instantly. Upload a STEP file to get a price and a DFM check.
Sources
- ASTM B584 — Copper Alloy Sand Castings for General Applications — ASTM International (2022)
- ASTM B505/B505M — Copper Alloy Continuous Castings — ASTM International (2018)
- ASTM B271 — Copper-Base Alloy Centrifugal Castings — ASTM International (2020)
- CDA Alloy Datasheet C84400 — Copper Development Association (copper.org) (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.