Copper Alloy CC490K-GM (Gravity (permanent) die cast)
Finish state
EN CC490K
Choose for medium-to-high volume fittings needing better surface finish, tighter tolerance and a finer, slightly stronger structure than sand casting.
Values for the GM condition
Other CC490K tempers and conditions
CC490K is listed in 4 conditions; see the grade overview at CC490K.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
GSDefault Sand cast | General-purpose route for valve bodies, pump housings and one-off or low-volume complex shapes. | 100 | 215 | 20 | 65 HB | 15 % IACS |
Centrifugally cast | Use for bushes, sleeves and rings where a dense, low-porosity wall and pressure tightness matter. | 105 | 225 | 16 | 68 HB | 16 % IACS |
GMThis page Gravity (permanent) die cast | Choose for medium-to-high volume fittings needing better surface finish, tighter tolerance and a finer, slightly stronger structure than sand casting. | 110 | 225 | 16 | 70 HB | 16 % IACS |
Continuously cast | Bar, tube and hollow stock for machined bushings and fittings — highest strength and hardness of the four routes thanks to directional, sound solidification. | 130 | 250 | 12 | 75 HB | 17 % IACS |
What is CC490K-GM?
CC490K-GM is CC490K supplied in the GM condition — choose for medium-to-high volume fittings needing better surface finish, tighter tolerance and a finer, slightly stronger structure than sand casting. CC490K-GM has a yield strength of 110 MPa (16 ksi) and a tensile strength of 225 MPa (32.6 ksi) — weaker than 82% of copper alloy grades. Elongation at break is 16% and the elastic modulus is 95 GPa (13.8 Msi). CC490K-GM has a density of 8.7 g/cm³ (0.314 lb/in³), lighter than 56% of copper alloy grades. It melts at 900°C (1,652 °F). GS is the default condition FabDigit quotes; GM is available on request or by drawing note.
Advantages
- Easy to machine — 80/100, better than 86% 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
- Low strength — 110 MPa (16 ksi), worse than 82% of copper alloy grades
- Difficult to weld — 25/100, worse than 78% of copper alloy grades
CC490K-GM properties
Typical room-temperature values for CC490K-GM; 20 are specific to this condition. Other listed values are CC490K reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
CC490K-GM has a density of 8.7 g/cm³ (0.314 lb/in³), lighter than 56% of copper alloy grades. It melts at 900°C (1,652 °F).
Mechanical14
CC490K-GM has a yield strength of 110 MPa (16 ksi) and a tensile strength of 225 MPa (32.6 ksi) — weaker than 82% of copper alloy grades. Elongation at break is 16% and the elastic modulus is 95 GPa (13.8 Msi).
Thermal6
CC490K-GM is rated for continuous service to 200°C (392 °F). It conducts heat at 80 W/m·K (46.2 BTU/hr·ft·°F), better than 50% of copper alloy grades. Thermal expansion is 18.5 µm/m·K (10.3 µin/in·°F).
Electrical3
CC490K-GM conducts electricity at 16 % IACS, worse than 52% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is very good (70/100), better than 76% of copper alloy grades.
Sustainability4
Producing a kilogram of CC490K-GM takes about 55 MJ of energy and emits 3.6 kg of CO₂ — less than 72% of copper alloy grades. Typical recycled content is 85%.
Manufacturability7
CC490K-GM's machinability is very good (80/100, better than 86% of copper alloy grades); weldability poor (25/100); formability not recommended (10/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with CC490K-GM
Is CC490K easy to machine?
Excellent free-machining behaviour from the lead phase — high speeds, light positive-rake tooling, chips break cleanly; watch lead dust/fume hygiene.
Can CC490K be welded?
Not recommended for fusion welding (lead causes hot cracking); repair by brazing or soft soldering, or use mechanical joints.
Can CC490K be formed, bent or molded?
Casting alloy only: good fluidity and pressure tightness in sand, permanent-mould, centrifugal and continuous casting; allow ~1.5 % shrinkage and use chills on heavy sections.
What surface finishes work on CC490K?
Takes soft solder and nickel/chrome plating readily after careful degreasing; polishes to a satin lustre but lead smear and micro-porosity limit a true mirror finish; anodizing not applicable.
CC490K 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 |
|---|---|---|
| Sn | 2 – 4 | 3 |
| Zn | 7 – 9.5 | 8 |
| Pbfree-machining and pressure-tightness additive | 4 – 6 | 5 |
| Niincidental/permitted | ≤ 2 | — |
| Fe | ≤ 0.3 | — |
| Sb | ≤ 0.25 | — |
| P | ≤ 0.05 | — |
| S | ≤ 0.1 | — |
| Alkept low to avoid casting defects | ≤ 0.01 | — |
| Si | ≤ 0.01 | — |
| Curemainder, approx. 82–87 % | balance | — |
CC490K-GM — frequently asked
What is CC490K-GM used for?
CC490K-GM is typically used for valve bodies, pump housings, plumbing fittings and pressure-tight castings. In short: pressure-tight gunmetal casting alloy; free-cutting cast bronze; sand to continuous cast forms.
What is the yield strength of CC490K-GM?
CC490K-GM has a typical yield strength of 110 MPa (16 ksi) and a tensile strength of 225 MPa (32.6 ksi) — weaker than 82% of copper alloy grades. Strength varies by condition: see the 4 listed tempers.
Is CC490K-GM easy to machine?
Yes — machinability is rated very good (80/100, better than 86% of copper alloy grades). Excellent free-machining behaviour from the lead phase — high speeds, light positive-rake tooling, chips break cleanly; watch lead dust/fume hygiene.
Can CC490K-GM be welded?
Not readily — weldability is rated poor (25/100). Not recommended for fusion welding (lead causes hot cracking); repair by brazing or soft soldering, or use mechanical joints.
What surface finishes work on CC490K-GM?
Takes soft solder and nickel/chrome plating readily after careful degreasing; polishes to a satin lustre but lead smear and micro-porosity limit a true mirror finish; anodizing not applicable.
Can CC490K-GM be formed, bent or molded?
Casting alloy only: good fluidity and pressure tightness in sand, permanent-mould, centrifugal and continuous casting; allow ~1.5 % shrinkage and use chills on heavy sections.
What is the maximum service temperature of CC490K-GM?
CC490K-GM 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 CC490K-GS and CC490K-GC?
GS is the default condition — general-purpose route for valve bodies, pump housings and one-off or low-volume complex shapes. GC: bar, tube and hollow stock for machined bushings and fittings — highest strength and hardness of the four routes thanks to directional, sound solidification. Yield strength is 100 MPa in GS versus 130 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)
- CDA alloy datasheet C83450 / leaded red brass casting alloys — Copper Development Association (2023)
- ASTM B584 — Copper Alloy Sand Castings for General Applications — ASTM (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.