Copper Alloy CC498K-GM (Permanent (chill) mould cast)
Finish state
EN CC498K
Choose for medium-to-large series of small parts needing finer grain, tighter tolerances and slightly higher strength than sand casting.
Values for the GM condition
Other CC498K tempers and conditions
CC498K is listed in 4 conditions; see the grade overview at CC498K.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Sand cast | Choose for one-off or large, complex housings, valve bodies and pump casings where dimensional tolerance is less critical. | 110 | 230 | 15 | 65 HB | 12 % IACS |
GMThis page Permanent (chill) mould cast | Choose for medium-to-large series of small parts needing finer grain, tighter tolerances and slightly higher strength than sand casting. | 130 | 260 | 13 | 72 HB | 12 % IACS |
Centrifugally cast | Choose for large-diameter bushings, wear rings and worm-wheel rims where a dense, porosity-free wall is required. | 140 | 270 | 13 | 75 HB | 12 % IACS |
GCDefault Continuously cast bar/tube | Default stock form: continuous-cast round bar and tube for machined bushings, nuts, glands and guide elements — densest structure and best machined surface. | 150 | 270 | 12 | 78 HB | 12.5 % IACS |
What is CC498K-GM?
CC498K-GM is CC498K supplied in the GM condition — choose for medium-to-large series of small parts needing finer grain, tighter tolerances and slightly higher strength than sand casting. CC498K-GM has a yield strength of 130 MPa (18.9 ksi) and a tensile strength of 260 MPa (37.7 ksi) — weaker than 77% of copper alloy grades. Elongation at break is 13% and the elastic modulus is 92 GPa (13.3 Msi). CC498K-GM has a density of 8.8 g/cm³ (0.318 lb/in³), heavier than 58% of copper alloy grades. It melts at 855°C (1,571 °F). GC 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 — 92 GPa (13.3 Msi), worse than 94% of copper alloy grades
- Limited formability — 10/100, worse than 89% of copper alloy grades
- Low strength — 130 MPa (18.9 ksi), worse than 77% of copper alloy grades
CC498K-GM properties
Typical room-temperature values for CC498K-GM; 20 are specific to this condition. Other listed values are CC498K reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
CC498K-GM has a density of 8.8 g/cm³ (0.318 lb/in³), heavier than 58% of copper alloy grades. It melts at 855°C (1,571 °F).
Mechanical14
CC498K-GM has a yield strength of 130 MPa (18.9 ksi) and a tensile strength of 260 MPa (37.7 ksi) — weaker than 77% of copper alloy grades. Elongation at break is 13% and the elastic modulus is 92 GPa (13.3 Msi).
Thermal6
CC498K-GM is rated for continuous service to 250°C (482 °F). It conducts heat at 60 W/m·K (34.7 BTU/hr·ft·°F), worse than 59% of copper alloy grades. Thermal expansion is 18.5 µm/m·K (10.3 µin/in·°F).
Electrical3
CC498K-GM conducts electricity at 12 % IACS, worse than 62% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is good (65/100), better than 58% of copper alloy grades.
Sustainability4
Producing a kilogram of CC498K-GM takes about 50 MJ of energy and emits 3.5 kg of CO₂ — less than 89% of copper alloy grades. Typical recycled content is 60%.
Manufacturability8
CC498K-GM's machinability is very good (80/100, better than 86% of copper alloy grades); weldability poor (30/100); formability not recommended (10/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with CC498K-GM
Is CC498K easy to machine?
Very free-machining thanks to the lead phase — use sharp positive-rake carbide or HSS tools, high speed, light feed and plenty of coolant; chips break short, so single-point boring of bushings gives excellent surface finish.
Can CC498K be welded?
Poor fusion weldability because lead causes hot cracking and porosity; repair by brazing or by TIG with matched Cu-Sn filler only after preheating and with acceptance of reduced properties.
Can CC498K be formed, bent or molded?
Foundry alloy with wide freezing range: feed generously with risers and chills to avoid interdendritic microporosity; not suitable for cold forming, only light coining/burnishing of machined bores.
What surface finishes work on CC498K?
Takes tin, nickel or chrome plating and chemical patination well; can be polished to a bright bronze lustre, but lead smearing may require light chemical bright-dip before plating.
CC498K 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 | 5 – 7 | 6 |
| Zn | 3 – 5 | 4 |
| Pbfree-machining / conformability addition | 1 – 3 | 2 |
| Niimpurity limit, Ni counted with Co | ≤ 2 | — |
| Feimpurity | ≤ 0.3 | — |
| Sbimpurity | ≤ 0.3 | — |
| Pimpurity | ≤ 0.1 | — |
| Simpurity | ≤ 0.1 | — |
| Alimpurity, harmful to castability | ≤ 0.01 | — |
| Siimpurity | ≤ 0.01 | — |
| Curemainder, typically 85–89 % | balance | — |
CC498K-GM — frequently asked
What is CC498K-GM used for?
CC498K-GM is typically used for valve bodies, pump housings, fittings and flanges, general hardware castings and low-to-moderate load bearing components. In short: free-machining cast bronze; stronger than gunmetal CC499K; poor fusion weldability.
What is the yield strength of CC498K-GM?
CC498K-GM has a typical yield strength of 130 MPa (18.9 ksi) and a tensile strength of 260 MPa (37.7 ksi) — weaker than 77% of copper alloy grades. Strength varies by condition: see the 4 listed tempers.
Is CC498K-GM easy to machine?
Yes — machinability is rated very good (80/100, better than 86% of copper alloy grades). Very free-machining thanks to the lead phase — use sharp positive-rake carbide or HSS tools, high speed, light feed and plenty of coolant; chips break short, so single-point boring of bushings gives excellent surface finish.
Can CC498K-GM be welded?
Not readily — weldability is rated poor (30/100). Poor fusion weldability because lead causes hot cracking and porosity; repair by brazing or by TIG with matched Cu-Sn filler only after preheating and with acceptance of reduced properties.
What surface finishes work on CC498K-GM?
Takes tin, nickel or chrome plating and chemical patination well; can be polished to a bright bronze lustre, but lead smearing may require light chemical bright-dip before plating.
Can CC498K-GM be formed, bent or molded?
Foundry alloy with wide freezing range: feed generously with risers and chills to avoid interdendritic microporosity; not suitable for cold forming, only light coining/burnishing of machined bores.
What is the maximum service temperature of CC498K-GM?
CC498K-GM is rated for continuous use to about 250°C (482 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between CC498K-GC and CC498K-GS?
GC is the default condition — default stock form: continuous-cast round bar and tube for machined bushings, nuts, glands and guide elements — densest structure and best machined surface. GS: choose for one-off or large, complex housings, valve bodies and pump casings where dimensional tolerance is less critical. Yield strength is 150 MPa in GC versus 110 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.org cast bronze alloy datasheets — Copper Development Association (2023)
- Continuous-cast leaded tin bronze bushing bar datasheets — European and Chinese bronze foundries (2024)
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.