Copper Alloy ZCuAl9Mn2-SR (Stress relieved)
Heat-treated state
Used after welding or heavy machining to relieve residual stress and improve dimensional stability; slightly softens the casting.
Values for the SR condition
Other ZCuAl9Mn2 tempers and conditions
ZCuAl9Mn2 is listed in 5 conditions; see the grade overview at ZCuAl9Mn2.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
SRThis page Stress relieved | Used after welding or heavy machining to relieve residual stress and improve dimensional stability; slightly softens the casting. | 155 | 410 | 30 | 88 HB | 13.5 % IACS |
SDefault Sand cast | Standard general-purpose condition for medium and large marine/industrial castings. | 165 | 430 | 25 | 95 HB | 13 % IACS |
Permanent (metal) mould cast, as-cast | Chill-cast smaller parts: finer grain gives ~10 % higher strength and hardness than sand cast. | 190 | 480 | 24 | 105 HB | 13 % IACS |
Centrifugally cast | Choose for bushings, sleeves and worm-wheel rims where a dense, inclusion-free wall is needed. | 195 | 490 | 25 | 108 HB | 13 % IACS |
Continuously cast bar / tube | Stock bar and hollow for machined bushings, nuts and valve parts; most uniform and lowest-porosity form. | 200 | 500 | 22 | 110 HB | 13 % IACS |
What is ZCuAl9Mn2-SR?
ZCuAl9Mn2-SR is ZCuAl9Mn2 heat treated to SR — used after welding or heavy machining to relieve residual stress and improve dimensional stability; slightly softens the casting. ZCuAl9Mn2-SR has a yield strength of 155 MPa (22.5 ksi) and a tensile strength of 410 MPa (59.5 ksi) — weaker than 65% of copper alloy grades. Elongation at break is 30% and the elastic modulus is 110 GPa (16 Msi). ZCuAl9Mn2-SR has a density of 7.6 g/cm³ (0.275 lb/in³), lighter than 93% of copper alloy grades. It melts at 1,040°C (1,904 °F). S is the default condition FabDigit quotes; SR is available on request or by drawing note.
Advantages
- Lightweight — 7.6 g/cm³ (0.275 lb/in³), better than 93% of copper alloy grades
- Readily welded — 74/100, better than 88% 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
- Ductile — tolerates forming and impact — 30%, better than 75% of copper alloy grades
ZCuAl9Mn2-SR properties
Typical room-temperature values for ZCuAl9Mn2-SR; 20 are specific to this condition. Other listed values are ZCuAl9Mn2 reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
ZCuAl9Mn2-SR has a density of 7.6 g/cm³ (0.275 lb/in³), lighter than 93% of copper alloy grades. It melts at 1,040°C (1,904 °F).
Mechanical16
ZCuAl9Mn2-SR has a yield strength of 155 MPa (22.5 ksi) and a tensile strength of 410 MPa (59.5 ksi) — weaker than 65% of copper alloy grades. Elongation at break is 30% and the elastic modulus is 110 GPa (16 Msi).
Thermal6
ZCuAl9Mn2-SR is rated for continuous service to 300°C (572 °F). It conducts heat at 54 W/m·K (31.2 BTU/hr·ft·°F), worse than 64% of copper alloy grades. Thermal expansion is 16.8 µm/m·K (9.33 µin/in·°F).
Electrical3
ZCuAl9Mn2-SR conducts electricity at 13.5 % IACS, worse than 56% 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 ZCuAl9Mn2-SR takes about 55 MJ of energy and emits 3.8 kg of CO₂ — less than 72% of copper alloy grades. Typical recycled content is 65%.
Manufacturability8
ZCuAl9Mn2-SR's machinability is fair (42/100, better than 59% of copper alloy grades); weldability very good (74/100); formability fair (35/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with ZCuAl9Mn2-SR
Is ZCuAl9Mn2 easy to machine?
Machines like a tough ductile bronze — use sharp positive-rake carbide, moderate speed (60–120 m/min), heavy feed and generous coolant to break stringy chips; avoid dwelling to prevent work hardening.
Can ZCuAl9Mn2 be welded?
Readily GTAW/GMAW welded with matching Al-bronze filler (ER CuAl-A2 type) under argon; clean the alumina film mechanically before welding and preheat 150–250 °C on heavy sections, then stress relieve.
Can ZCuAl9Mn2 be formed, bent or molded?
Foundry alloy: bottom-gate with generous filtration and non-turbulent fill to avoid oxide skins, feed with adequate risers because of the wide-ish freezing range and high shrinkage (~1.8–2 %).
What surface finishes work on ZCuAl9Mn2?
Cannot be anodized; polishes to a bright golden surface, and can be sand-blasted, chemically passivated or protected with clear lacquer/epoxy for marine service.
ZCuAl9Mn2 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 |
|---|---|---|
| Alprincipal strengthening element | 8 – 10 | 9 |
| Mnsolid-solution strengthening, deoxidation | 1.5 – 2.5 | 2 |
| Feimpurity limit | ≤ 1 | — |
| Znimpurity limit | ≤ 1.5 | — |
| Siimpurity limit | ≤ 0.2 | — |
| Snimpurity limit | ≤ 0.2 | — |
| Pbimpurity limit | ≤ 0.1 | — |
| Cubalance, ≈88–90% | balance | — |
ZCuAl9Mn2-SR — frequently asked
What is ZCuAl9Mn2-SR used for?
ZCuAl9Mn2-SR is typically used for pump impellers, valve bodies and marine hardware. In short: ductile aluminium bronze; good seawater resistance; weldable cast bronze.
What is the yield strength of ZCuAl9Mn2-SR?
ZCuAl9Mn2-SR has a typical yield strength of 155 MPa (22.5 ksi) and a tensile strength of 410 MPa (59.5 ksi) — weaker than 65% of copper alloy grades. Strength varies by condition: see the 5 listed tempers.
Is ZCuAl9Mn2-SR easy to machine?
Not especially — machinability is rated fair (42/100, better than 59% of copper alloy grades). Machines like a tough ductile bronze — use sharp positive-rake carbide, moderate speed (60–120 m/min), heavy feed and generous coolant to break stringy chips; avoid dwelling to prevent work hardening.
Can ZCuAl9Mn2-SR be welded?
Yes — weldability is rated very good (74/100). Readily GTAW/GMAW welded with matching Al-bronze filler (ER CuAl-A2 type) under argon; clean the alumina film mechanically before welding and preheat 150–250 °C on heavy sections, then stress relieve.
What surface finishes work on ZCuAl9Mn2-SR?
Cannot be anodized; polishes to a bright golden surface, and can be sand-blasted, chemically passivated or protected with clear lacquer/epoxy for marine service.
Can ZCuAl9Mn2-SR be formed, bent or molded?
Foundry alloy: bottom-gate with generous filtration and non-turbulent fill to avoid oxide skins, feed with adequate risers because of the wide-ish freezing range and high shrinkage (~1.8–2 %).
What is the maximum service temperature of ZCuAl9Mn2-SR?
ZCuAl9Mn2-SR 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 ZCuAl9Mn2-S and ZCuAl9Mn2-La?
S is the default condition — standard general-purpose condition for medium and large marine/industrial castings. La: stock bar and hollow for machined bushings, nuts and valve parts; most uniform and lowest-porosity form. Yield strength is 165 MPa in S versus 200 MPa in La.
Sources
- EN 1982 Copper and copper alloys — Ingots and castings — CEN (2017)
- ASM Handbook Vol. 2: Properties and Selection — Nonferrous Alloys (Aluminum Bronzes) — ASM International (1990)
- CDA alloy datasheets, C95200/C95300 cast aluminium bronze — Copper Development Association (2020)
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.