Copper Alloy C61800-TQ50
Supply condition
UNS C61800 · ASTM B150 · EN CW305G · GB QAl9-4
TQ50 = quench hardened and tempered
Use at the high-aluminium end of the range when maximum strength and wear resistance are needed for bushings, gears and valve stems.
Values for the TQ50 condition
Other C61800 tempers and conditions
C61800 is listed in 5 conditions; see the grade overview at C61800.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Soft annealed | Choose for maximum ductility before severe forming, bending or deep drawing of rod/plate. | 210 | 520 | 40 | 140 HB | 14 % IACS |
M30Default As hot extruded | The standard stocked condition for round bar, hex and shapes — balanced strength, ductility and cost. | 275 | 585 | 30 | 170 HB | — |
Hot rolled / hot worked plate and flats | Plate, flat bar and forged shapes supplied in the as-hot-worked condition for marine structural parts. | 300 | 600 | 26 | 175 HB | 13 % IACS |
Full hard | Pick for higher yield strength, better surface finish and tighter tolerance on small-diameter rod, shafts and fasteners. | 415 | 655 | 18 | 13 HRC | 12.5 % IACS |
TQ50This page Quench hardened and tempered | Use at the high-aluminium end of the range when maximum strength and wear resistance are needed for bushings, gears and valve stems. | 450 | 725 | 12 | 22 HRC | 12 % IACS |
What is C61800-TQ50?
C61800-TQ50 is C61800 supplied in the TQ50 condition — use at the high-aluminium end of the range when maximum strength and wear resistance are needed for bushings, gears and valve stems. C61800-TQ50 has a yield strength of 450 MPa (65.3 ksi) and a tensile strength of 725 MPa (105 ksi) — stronger than 86% of copper alloy grades. Elongation at break is 12% and the elastic modulus is 117 GPa (17 Msi). C61800-TQ50 has a density of 7.58 g/cm³ (0.274 lb/in³), lighter than 94% of copper alloy grades. It melts at 1,043°C (1,909 °F). M30 is the default condition FabDigit quotes; TQ50 is available on request or by drawing note.
Advantages
- Lightweight — 7.58 g/cm³ (0.274 lb/in³), better than 94% of copper alloy grades
- High strength — 450 MPa (65.3 ksi), better than 86% of copper alloy grades
- High service temperature — 300°C (572 °F), better than 85% of copper alloy grades
- Good corrosion resistance — 72/100, better than 84% of copper alloy grades
Limitations
- Difficult to machine — 24/100, worse than 91% of copper alloy grades
C61800-TQ50 properties
Typical room-temperature values for C61800-TQ50; 23 are specific to this condition. Other listed values are C61800 reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
C61800-TQ50 has a density of 7.58 g/cm³ (0.274 lb/in³), lighter than 94% of copper alloy grades. It melts at 1,043°C (1,909 °F).
Mechanical16
C61800-TQ50 has a yield strength of 450 MPa (65.3 ksi) and a tensile strength of 725 MPa (105 ksi) — stronger than 86% of copper alloy grades. Elongation at break is 12% and the elastic modulus is 117 GPa (17 Msi).
Thermal6
C61800-TQ50 is rated for continuous service to 300°C (572 °F). It conducts heat at 53 W/m·K (30.6 BTU/hr·ft·°F), worse than 64% of copper alloy grades. Thermal expansion is 16.2 µm/m·K (9 µin/in·°F).
Electrical3
C61800-TQ50 conducts electricity at 12 % IACS, worse than 62% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is very good (72/100), better than 84% of copper alloy grades.
Sustainability4
Producing a kilogram of C61800-TQ50 takes about 55 MJ of energy and emits 3.7 kg of CO₂ — less than 72% of copper alloy grades. Typical recycled content is 40%.
Manufacturability8
C61800-TQ50's machinability is poor (24/100, worse than 91% of copper alloy grades); weldability good (55/100); formability poor (20/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with C61800-TQ50
Is C61800 easy to machine?
Tough, gummy chips — use rigid setups, sharp positive-rake carbide, moderate speed (60–90 m/min) with heavy flood coolant; rating ≈40 % of AISI 1212.
Can C61800 be welded?
Readily GTAW/GMAW welded with matching ERCuAl-A2 filler; remove the alumina film mechanically or with AC/He cleaning and keep interpass temperature low.
Can C61800 be formed, bent or molded?
Hot work at 700–850 °C; cold bending is limited (fair formability), so anneal at 620–670 °C with fast cooling between severe cold-forming steps.
What surface finishes work on C61800?
Not anodisable — finish by machining/polishing to a golden lustre, or apply clear lacquer; electroplating requires thorough oxide removal and a nickel strike.
C61800 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 |
|---|---|---|
| Al | 8.5 – 11 | 9.5 |
| Fe | 0.5 – 1.5 | 1 |
| Si | ≤ 0.1 | — |
| Zn | ≤ 0.02 | — |
| Pb | ≤ 0.02 | — |
| CuCu + named elements 99.5 % min | balance | — |
C61800-TQ50 — frequently asked
What is C61800-TQ50 used for?
C61800-TQ50 is typically used for marine fasteners, pump shafts, corrosion-resistant fittings and bushings. In short: general-purpose aluminum bronze; strong seawater resistance; weldable but gummy to machine.
What is the yield strength of C61800-TQ50?
C61800-TQ50 has a typical yield strength of 450 MPa (65.3 ksi) and a tensile strength of 725 MPa (105 ksi) — stronger than 86% of copper alloy grades. Strength varies by condition: see the 5 listed tempers.
Is C61800-TQ50 easy to machine?
Not especially — machinability is rated poor (24/100, worse than 91% of copper alloy grades). Tough, gummy chips — use rigid setups, sharp positive-rake carbide, moderate speed (60–90 m/min) with heavy flood coolant; rating ≈40 % of AISI 1212.
Can C61800-TQ50 be welded?
Yes — weldability is rated good (55/100). Readily GTAW/GMAW welded with matching ERCuAl-A2 filler; remove the alumina film mechanically or with AC/He cleaning and keep interpass temperature low.
What surface finishes work on C61800-TQ50?
Not anodisable — finish by machining/polishing to a golden lustre, or apply clear lacquer; electroplating requires thorough oxide removal and a nickel strike.
Can C61800-TQ50 be formed, bent or molded?
Hot work at 700–850 °C; cold bending is limited (fair formability), so anneal at 620–670 °C with fast cooling between severe cold-forming steps.
What is the maximum service temperature of C61800-TQ50?
C61800-TQ50 is rated for continuous use to about 300°C (572 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between C61800-M30 and C61800-TQ50?
M30 is the default condition — the standard stocked condition for round bar, hex and shapes — balanced strength, ductility and cost. TQ50: use at the high-aluminium end of the range when maximum strength and wear resistance are needed for bushings, gears and valve stems. Yield strength is 275 MPa in M30 versus 450 MPa in TQ50.
Sources
- ASTM B150/B150M — Aluminum Bronze Rod, Bar and Shapes — ASTM International (2019)
- EN 12163 / CW305G copper alloy rod — CEN (2016)
- GB/T 4423 / GB/T 1176 (QAl9-4) — SAC (2020)
- CDA Alloy Datasheet C61800 — Copper Development Association (2023)
- ASM Handbook Vol. 2 — Properties of Nonferrous Alloys — ASM International (1990)
- ASM Handbook Vol. 13B — Corrosion: Materials — ASM International (2005)
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.