Copper Alloy CC755S-GS (Sand cast)
Finish state
EN CC755S
Choose for larger, low-volume or one-off housings and valve bodies where thin-wall detail is not critical.
Values for the GS condition
Other CC755S tempers and conditions
CC755S is listed in 4 conditions; see the grade overview at CC755S.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
GSThis page Sand cast | Choose for larger, low-volume or one-off housings and valve bodies where thin-wall detail is not critical. | 135 | 355 | 22 | 90 HB | 23 % IACS |
GMDefault Gravity die cast | Default stock condition: best combination of surface finish, dimensional accuracy and strength for series water/valve fittings. | 150 | 370 | 22 | 95 HB | 24 % IACS |
Centrifugally cast | Choose for bushings, sleeves and rings needing dense, inclusion-free rotationally symmetric sections. | 155 | 385 | 22 | 100 HB | 24 % IACS |
Continuously cast | Choose for machined-from-bar parts: uniform fine structure, best soundness and consistent machining behaviour. | 155 | 385 | 20 | 100 HB | 25 % IACS |
What is CC755S-GS?
CC755S-GS is CC755S supplied in the GS condition — choose for larger, low-volume or one-off housings and valve bodies where thin-wall detail is not critical. CC755S-GS has a yield strength of 135 MPa (19.6 ksi) and a tensile strength of 355 MPa (51.5 ksi) — weaker than 76% of copper alloy grades. Elongation at break is 22% and the elastic modulus is 90 GPa (13.1 Msi). CC755S-GS has a density of 8.3 g/cm³ (0.3 lb/in³), lighter than 80% of copper alloy grades. It melts at 880°C (1,616 °F). GM is the default condition FabDigit quotes; GS is available on request or by drawing note.
Advantages
- Low embodied carbon — 3.1 kg CO₂/kg, better than 95% of copper alloy grades
- Easy to machine — 76/100, better than 81% of copper alloy grades
Limitations
- Low stiffness — 90 GPa (13.1 Msi), worse than 95% of copper alloy grades
- Needs corrosion protection — 50/100, worse than 95% 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
- Low strength — 135 MPa (19.6 ksi), worse than 76% of copper alloy grades
CC755S-GS properties
Typical room-temperature values for CC755S-GS; 21 are specific to this condition. Other listed values are CC755S reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
CC755S-GS has a density of 8.3 g/cm³ (0.3 lb/in³), lighter than 80% of copper alloy grades. It melts at 880°C (1,616 °F).
Mechanical15
CC755S-GS has a yield strength of 135 MPa (19.6 ksi) and a tensile strength of 355 MPa (51.5 ksi) — weaker than 76% of copper alloy grades. Elongation at break is 22% and the elastic modulus is 90 GPa (13.1 Msi).
Thermal6
CC755S-GS is rated for continuous service to 200°C (392 °F). It conducts heat at 108 W/m·K (62.4 BTU/hr·ft·°F), better than 58% of copper alloy grades. Thermal expansion is 21 µm/m·K (11.7 µin/in·°F).
Electrical3
CC755S-GS conducts electricity at 23 % IACS, better than 56% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is fair (50/100), worse than 95% of copper alloy grades.
Sustainability4
Producing a kilogram of CC755S-GS takes about 50 MJ of energy and emits 3.1 kg of CO₂ — less than 89% of copper alloy grades. Typical recycled content is 75%.
Manufacturability8
CC755S-GS's machinability is very good (76/100, better than 81% of copper alloy grades); weldability poor (25/100); formability poor (15/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with CC755S-GS
Is CC755S easy to machine?
Very free-machining with the 1 % Pb phase — use sharp positive-rake carbide or HSS, 0° to slight negative rake for brass, high speeds and light lubrication; expect short chips.
Can CC755S be welded?
Fusion welding is not recommended (Pb hot-cracking and Zn fuming); use brazing with silver filler, soldering or mechanical joining, and extract fumes.
Can CC755S be formed, bent or molded?
Casting alloy only — excellent fluidity for thin walls; boron refines grain and reduces gas porosity, degas the melt and use moderate pouring temperature (~1000–1050 °C).
What surface finishes work on CC755S?
Takes bright polishing, brushing, Ni/Cr or PVD plating and clear lacquer; do not anodize — for potable-water duty check lead-leaching regulations and consider a dezincification-resistant alternative.
CC755S 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 | 57 – 59 | 58 |
| Pbfree-machining phase | 0.5 – 1.5 | 1 |
| Alimproves fluidity and strength | 0.3 – 1 | 0.6 |
| Bgrain refiner / modifier — distinguishes CC755S from CuZn39Pb1Al-C | 0.01 – 0.06 | 0.02 |
| Fe | ≤ 0.8 | 0.3 |
| Sn | ≤ 0.5 | 0.2 |
| Ni | ≤ 1 | 0.2 |
| Mn | ≤ 0.5 | 0.1 |
| Si | ≤ 0.05 | — |
| Zn≈38–40 % | balance | — |
CC755S-GS — frequently asked
What is CC755S-GS used for?
CC755S-GS is typically used for precision fittings, hardware castings and valve parts. In short: boron grain-refined cast brass; thin-wall casting grade; very free-machining.
What is the yield strength of CC755S-GS?
CC755S-GS has a typical yield strength of 135 MPa (19.6 ksi) and a tensile strength of 355 MPa (51.5 ksi) — weaker than 76% of copper alloy grades. Strength varies by condition: see the 4 listed tempers.
Is CC755S-GS easy to machine?
Yes — machinability is rated very good (76/100, better than 81% of copper alloy grades). Very free-machining with the 1 % Pb phase — use sharp positive-rake carbide or HSS, 0° to slight negative rake for brass, high speeds and light lubrication; expect short chips.
Can CC755S-GS be welded?
Not readily — weldability is rated poor (25/100). Fusion welding is not recommended (Pb hot-cracking and Zn fuming); use brazing with silver filler, soldering or mechanical joining, and extract fumes.
What surface finishes work on CC755S-GS?
Takes bright polishing, brushing, Ni/Cr or PVD plating and clear lacquer; do not anodize — for potable-water duty check lead-leaching regulations and consider a dezincification-resistant alternative.
Can CC755S-GS be formed, bent or molded?
Casting alloy only — excellent fluidity for thin walls; boron refines grain and reduces gas porosity, degas the melt and use moderate pouring temperature (~1000–1050 °C).
What is the maximum service temperature of CC755S-GS?
CC755S-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 CC755S-GM and CC755S-GS?
GM is the default condition — default stock condition: best combination of surface finish, dimensional accuracy and strength for series water/valve fittings. GS: choose for larger, low-volume or one-off housings and valve bodies where thin-wall detail is not critical. Yield strength is 150 MPa in GM versus 135 MPa in GS.
Sources
- EN 1982 — Copper and copper alloys: Ingots and castings — CEN (2017)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- CDA copper alloy datasheets (cast leaded brasses) — Copper Development Association (2023)
- European brass foundry alloy datasheets (CuZn39Pb1Al-C family) — various foundries (2022)
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.