Copper Alloy CC766S-GS (Sand cast)
Finish state · default condition
EN CC766S
Default general-engineering condition: one-off and low-volume castings, thick sections, largest parts.
Values for the GS condition
Other CC766S tempers and conditions
CC766S is listed in 4 conditions; see the grade overview at CC766S.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
GSDefaultThis page Sand cast | Default general-engineering condition: one-off and low-volume castings, thick sections, largest parts. | 155 | 400 | 20 | 95 HB | 22 % IACS |
Gravity die cast | Choose for repeat production of small/medium parts: finer grain, higher strength and better surface than sand casting. | 175 | 440 | 16 | 105 HB | 22 % IACS |
Centrifugally cast | Pick for rings, bushes, sleeves and hollow bodies needing dense, porosity-free walls. | 180 | 450 | 16 | 105 HB | 22 % IACS |
Continuously cast bar/tube | Semi-finished bar, tube and hollow stock for machined components; most uniform structure and best machining stock removal. | 185 | 450 | 15 | 110 HB | 22.5 % IACS |
What is CC766S-GS?
CC766S-GS is CC766S supplied in the GS condition — default general-engineering condition: one-off and low-volume castings, thick sections, largest parts. CC766S-GS has a yield strength of 155 MPa (22.5 ksi) and a tensile strength of 400 MPa (58 ksi) — weaker than 65% of copper alloy grades. Elongation at break is 20% and the elastic modulus is 95 GPa (13.8 Msi). CC766S-GS has a density of 8.35 g/cm³ (0.302 lb/in³), lighter than 77% of copper alloy grades. It melts at 885°C (1,625 °F).
Limitations
- Low stiffness — 95 GPa (13.8 Msi), worse than 93% of copper alloy grades
- Low fracture toughness — 35 MPa·√m (31.9 ksi·√in), worse than 79% of copper alloy grades
CC766S-GS properties
Typical room-temperature values for CC766S-GS; 21 are specific to this condition. Other listed values are CC766S reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
CC766S-GS has a density of 8.35 g/cm³ (0.302 lb/in³), lighter than 77% of copper alloy grades. It melts at 885°C (1,625 °F).
Mechanical15
CC766S-GS has a yield strength of 155 MPa (22.5 ksi) and a tensile strength of 400 MPa (58 ksi) — weaker than 65% of copper alloy grades. Elongation at break is 20% and the elastic modulus is 95 GPa (13.8 Msi).
Thermal6
CC766S-GS is rated for continuous service to 200°C (392 °F). It conducts heat at 102 W/m·K (58.9 BTU/hr·ft·°F), better than 55% of copper alloy grades. Thermal expansion is 20.5 µm/m·K (11.4 µin/in·°F).
Electrical3
CC766S-GS conducts electricity at 22 % IACS, better than 55% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is good (56/100), worse than 81% of copper alloy grades.
Sustainability4
Producing a kilogram of CC766S-GS takes about 55 MJ of energy and emits 3.6 kg of CO₂ — less than 72% of copper alloy grades. Typical recycled content is 70%.
Manufacturability8
CC766S-GS's machinability is fair (45/100, better than 64% of copper alloy grades); weldability fair (35/100); formability poor (30/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with CC766S-GS
Is CC766S easy to machine?
Machines like a medium-duty unleaded brass (~45 % of free-cutting brass): use sharp positive-rake carbide, high speed, light feeds and generous coolant to avoid gummy chips.
Can CC766S be welded?
Fusion welding is difficult — zinc volatilises and the Al oxide film traps slag; prefer TIG with Al-bronze/Si-bronze filler, preheat 150–200 °C, or repair by brazing with strong fluxing.
Can CC766S be formed, bent or molded?
A foundry alloy: pour at ~1000–1050 °C with good degassing and chills, allow generous fillets; the as-cast duplex structure has little cold formability, so shape by casting/machining.
What surface finishes work on CC766S?
Polishes and buffs to a bright brass tone, takes Ni/Cr and Sn plating after Al-oxide removal (acid or cyanide-free activation); not anodisable — protect with lacquer or patination for outdoor use.
CC766S 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 | 60 – 65 | 62 |
| Alprincipal strengthener; forms protective oxide film | 0.5 – 1.5 | 1 |
| Mn | ≤ 0.5 | 0.2 |
| Fe | ≤ 0.8 | 0.3 |
| Ni | ≤ 0.5 | — |
| Sn | ≤ 0.4 | — |
| Pbimpurity level only; not a free-cutting alloy | ≤ 0.5 | — |
| Si | ≤ 0.1 | — |
| Znremainder, nominally ~37 % | balance | — |
CC766S-GS — frequently asked
What is CC766S-GS used for?
CC766S-GS is typically used for water fittings, hardware castings and general engineering parts. In short: aluminium-strengthened yellow brass; general-purpose cast brass; medium-duty unleaded machining.
What is the yield strength of CC766S-GS?
CC766S-GS has a typical yield strength of 155 MPa (22.5 ksi) and a tensile strength of 400 MPa (58 ksi) — weaker than 65% of copper alloy grades. Strength varies by condition: see the 4 listed tempers.
Is CC766S-GS easy to machine?
Reasonably — machinability is rated fair (45/100, better than 64% of copper alloy grades). Machines like a medium-duty unleaded brass (~45 % of free-cutting brass): use sharp positive-rake carbide, high speed, light feeds and generous coolant to avoid gummy chips.
Can CC766S-GS be welded?
With care — weldability is rated fair (35/100). Fusion welding is difficult — zinc volatilises and the Al oxide film traps slag; prefer TIG with Al-bronze/Si-bronze filler, preheat 150–200 °C, or repair by brazing with strong fluxing.
What surface finishes work on CC766S-GS?
Polishes and buffs to a bright brass tone, takes Ni/Cr and Sn plating after Al-oxide removal (acid or cyanide-free activation); not anodisable — protect with lacquer or patination for outdoor use.
Can CC766S-GS be formed, bent or molded?
A foundry alloy: pour at ~1000–1050 °C with good degassing and chills, allow generous fillets; the as-cast duplex structure has little cold formability, so shape by casting/machining.
What is the maximum service temperature of CC766S-GS?
CC766S-GS 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 CC766S-GS and CC766S-GC?
GS is the default condition — default general-engineering condition: one-off and low-volume castings, thick sections, largest parts. GC: semi-finished bar, tube and hollow stock for machined components; most uniform structure and best machining stock removal. Yield strength is 155 MPa in GS versus 185 MPa in GC.
Sources
- EN 1982 — Copper and copper alloys: Ingots and castings — CEN (2017)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- Copper alloy datasheets (cast brasses) — Copper Development Association (2023)
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.