Copper Alloy CC751S
EN CC751S
CC751S (CuZn33Pb2Si-C) is a silicon-modified leaded yellow brass casting alloy in which the silicon addition raises melt fluidity and pressure tightness.
Reference datasheet — CC751S 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 GS condition
CC751S tempers and conditions
CC751S is supplied in 5 conditions, soft to hard. GS 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 |
|---|---|---|---|---|---|---|
GSDefault Sand cast | Standard sand-cast condition for general fittings, housings and one-off/low-volume parts. | 90 | 220 | 15 | 55 HB | 20 % IACS |
Gravity die (permanent mould) cast | Pick for medium/high volume fittings needing finer grain, better surface and higher strength than sand cast. | 110 | 270 | 12 | 65 HB | 20 % IACS |
Centrifugally cast | Use for bushings, rings and sleeves where a dense, inclusion-free wall is required. | 110 | 270 | 12 | 65 HB | 20 % IACS |
Continuously cast | Continuous-cast bar/tube stock for machined fittings and small pressure-tight bodies. | 120 | 280 | 12 | 70 HB | 20 % IACS |
Pressure (high-pressure) die cast | For high-volume thin-wall hardware where the silicon addition's fluidity and die-filling are exploited; check availability with the foundry. | 140 | 300 | 8 | 75 HB | 20 % IACS |
What is CC751S?
CC751S (CuZn33Pb2Si-C) is a silicon-modified leaded yellow brass casting alloy in which the silicon addition raises melt fluidity and pressure tightness. As-cast values are about 90 MPa yield, 220 MPa tensile, 15 % elongation and 55 HB, with 20 % IACS conductivity, and it is poured as sand (GS), gravity die (GM), centrifugal (GZ), continuous (GC) and pressure die (GP) castings for plumbing and sanitary fittings. Elongation and conductivity are lower than plain CC750S, fusion welding is not practical, and lead-restricted potable-water specifications may exclude it. CC750S is the nearer alternative for simple decorative hardware. CC751S has a density of 8.5 g/cm³ (0.307 lb/in³), lighter than 65% of copper alloy grades. It melts at 880°C (1,616 °F). CC751S has a yield strength of 90 MPa (13.1 ksi) and a tensile strength of 220 MPa (31.9 ksi) — weaker than 88% of copper alloy grades. Elongation at break is 15% and the elastic modulus is 90 GPa (13.1 Msi).
What is CC751S used for?
- plumbing fittings
- sanitary fittings
- general castings
Advantages
- Low embodied carbon — 3 kg CO₂/kg, better than 97% of copper alloy grades
- Easy to machine — 82/100, better than 90% of copper alloy grades
Limitations
- Low stiffness — 90 GPa (13.1 Msi), worse than 95% of copper alloy grades
- Low strength — 90 MPa (13.1 ksi), worse than 88% of copper alloy grades
- Difficult to weld — 20/100, worse than 88% of copper alloy grades
CC751S properties
Typical room-temperature values for CC751S-GS; bars are the position among copper alloy grades.
Physical3
CC751S has a density of 8.5 g/cm³ (0.307 lb/in³), lighter than 65% of copper alloy grades. It melts at 880°C (1,616 °F).
Mechanical15
CC751S has a yield strength of 90 MPa (13.1 ksi) and a tensile strength of 220 MPa (31.9 ksi) — weaker than 88% of copper alloy grades. Elongation at break is 15% and the elastic modulus is 90 GPa (13.1 Msi).
Thermal6
CC751S is rated for continuous service to 200°C (392 °F). It conducts heat at 110 W/m·K (63.6 BTU/hr·ft·°F), better than 58% of copper alloy grades. Thermal expansion is 20.5 µm/m·K (11.4 µin/in·°F).
Electrical3
CC751S conducts electricity at 20 % IACS, better than 52% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is good (57/100), worse than 80% of copper alloy grades.
Sustainability4
Producing a kilogram of CC751S takes about 45 MJ of energy and emits 3 kg of CO₂ — less than 97% of copper alloy grades. Typical recycled content is 75%.
Manufacturability8
CC751S's machinability is very good (82/100, better than 90% of copper alloy grades); weldability poor (20/100); formability poor (25/100).
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. CC751S is highlighted; hover a dot for its name, or open the interactive family chart.
Working with CC751S
Is CC751S easy to machine?
Excellent free-cutting behaviour (~80 % of AISI 1212): use zero/negative rake brass geometry, high speeds, light oil or dry, expect short chips.
Can CC751S be welded?
Not recommended for fusion welding (lead + zinc fume/hot cracking); repair by brazing or soft soldering, or mechanically fasten.
Can CC751S be formed, bent or molded?
Casting alloy only — silicon gives high fluidity and good pressure tightness for thin walls; feed with generous risers, degas melt and control zinc loss at low pour temperatures.
CC751S 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 |
|---|---|---|
| CuEN 1982 range | 63 – 67 | 65 |
| Pbfree-machining addition; restricted for potable-water use in some markets | 1 – 3 | 2 |
| Sifluidity / pressure-tightness addition | 0.2 – 0.8 | 0.5 |
| Snimpurity limit | ≤ 0.5 | |
| Feimpurity limit | ≤ 0.6 | |
| Niimpurity limit | ≤ 1 | |
| Alimpurity limit | ≤ 0.05 | |
| Mnimpurity limit | ≤ 0.2 | |
| Sbimpurity limit | ≤ 0.1 | |
| Znremainder, nominally ~33 % | balance |
What surface finishes work on CC751S?
Polishes and buffs well to a bright brass finish; readily nickel/chrome or bright-brass plated and lacquered; pickle/deburr to remove smeared lead 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 CC751S in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- EN / DIN / Werkstoff-Nr.
- CuZn33Pb2Si-C
How much does CC751S cost?
CC751S is a premium-cost copper alloy ($$$), cheaper than about 51% 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.
CC751S — frequently asked
What is CC751S used for?
CC751S is typically used for plumbing fittings, sanitary fittings and general castings. In short: silicon-boosted casting fluidity; thin-wall pressure-tight brass; 80 % free-cutting behaviour.
What is the yield strength of CC751S?
CC751S has a typical yield strength of 90 MPa (13.1 ksi) and a tensile strength of 220 MPa (31.9 ksi) — weaker than 88% of copper alloy grades. Strength varies by condition: see the 5 listed tempers.
Is CC751S easy to machine?
Yes — machinability is rated very good (82/100, better than 90% of copper alloy grades). Excellent free-cutting behaviour (~80 % of AISI 1212): use zero/negative rake brass geometry, high speeds, light oil or dry, expect short chips.
Can CC751S be welded?
Not readily — weldability is rated poor (20/100). Not recommended for fusion welding (lead + zinc fume/hot cracking); repair by brazing or soft soldering, or mechanically fasten.
What surface finishes work on CC751S?
Polishes and buffs well to a bright brass finish; readily nickel/chrome or bright-brass plated and lacquered; pickle/deburr to remove smeared lead before plating.
Can CC751S be formed, bent or molded?
Casting alloy only — silicon gives high fluidity and good pressure tightness for thin walls; feed with generous risers, degas melt and control zinc loss at low pour temperatures.
What is the maximum service temperature of CC751S?
CC751S 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 CC751S-GS and CC751S-GP?
GS is the default condition — standard sand-cast condition for general fittings, housings and one-off/low-volume parts. GP: for high-volume thin-wall hardware where the silicon addition's fluidity and die-filling are exploited; check availability with the foundry. Yield strength is 90 MPa in GS versus 140 MPa in GP.
How much does CC751S cost?
CC751S is a premium-cost copper alloy ($$$), cheaper than about 51% 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
- 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 leaded brasses) — Copper Development Association (2023)
- Cast brass alloy datasheets (CuZn33Pb2Si-C / CB751S) — European brass foundries / ingot makers (2023)
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.