Copper Alloy ZCuAl8Mn13Fe3Ni2-SR (Stress relieved)
Heat-treated state
UNS C95700
Applied to welded or heavily machined marine castings to relieve residual stress and reduce SCC risk, at a small cost in strength.
Values for the SR condition
Other ZCuAl8Mn13Fe3Ni2 tempers and conditions
ZCuAl8Mn13Fe3Ni2 is listed in 5 conditions; see the grade overview at ZCuAl8Mn13Fe3Ni2.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
SRThis page Stress relieved | Applied to welded or heavily machined marine castings to relieve residual stress and reduce SCC risk, at a small cost in strength. | 300 | 670 | 25 | 170 HB | 3.2 % IACS |
SDefault Sand cast | Standard supply condition for propellers, blades and large marine castings of any shape/size. | 320 | 690 | 22 | 10 HRC | 3 % IACS |
Centrifugal cast | Used for rings, large bushings and bearing sleeves needing sound, porosity-free walls. | 335 | 700 | 20 | 185 HB | 3 % IACS |
Permanent (metal) mould cast | Choose for smaller serial parts (bushings, valve bodies) where the faster chill gives finer structure and higher strength. | 340 | 715 | 20 | 12 HRC | 3 % IACS |
Continuous cast bar/tube | Best for machined bar and sleeve stock: dense, directionally solidified structure with the highest guaranteed strength. | 345 | 700 | 19 | 11 HRC | 3 % IACS |
What is ZCuAl8Mn13Fe3Ni2-SR?
ZCuAl8Mn13Fe3Ni2-SR is ZCuAl8Mn13Fe3Ni2 heat treated to SR — applied to welded or heavily machined marine castings to relieve residual stress and reduce SCC risk, at a small cost in strength. ZCuAl8Mn13Fe3Ni2-SR has a yield strength of 300 MPa (43.5 ksi) and a tensile strength of 670 MPa (97.2 ksi) — stronger than 61% of copper alloy grades. Elongation at break is 25% and the elastic modulus is 120 GPa (17.4 Msi). ZCuAl8Mn13Fe3Ni2-SR has a density of 7.53 g/cm³ (0.272 lb/in³), lighter than 96% of copper alloy grades. It melts at 870°C (1,598 °F). S is the default condition FabDigit quotes; SR is available on request or by drawing note.
Advantages
- Lightweight — 7.53 g/cm³ (0.272 lb/in³), better than 96% of copper alloy grades
- Good corrosion resistance — 78/100, better than 94% of copper alloy grades
- Tough — resists crack growth — 55 MPa·√m (50.1 ksi·√in), better than 85% of copper alloy grades
- High service temperature — 300°C (572 °F), better than 85% of copper alloy grades
- Readily welded — 65/100, better than 80% of copper alloy grades
Limitations
- Poor heat conductor — 12.5 W/m·K (7.22 BTU/hr·ft·°F), worse than 100% of copper alloy grades
- Low electrical conductivity — 3.2 % IACS, worse than 99% of copper alloy grades
ZCuAl8Mn13Fe3Ni2-SR properties
Typical room-temperature values for ZCuAl8Mn13Fe3Ni2-SR; 22 are specific to this condition. Other listed values are ZCuAl8Mn13Fe3Ni2 reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
ZCuAl8Mn13Fe3Ni2-SR has a density of 7.53 g/cm³ (0.272 lb/in³), lighter than 96% of copper alloy grades. It melts at 870°C (1,598 °F).
Mechanical16
ZCuAl8Mn13Fe3Ni2-SR has a yield strength of 300 MPa (43.5 ksi) and a tensile strength of 670 MPa (97.2 ksi) — stronger than 61% of copper alloy grades. Elongation at break is 25% and the elastic modulus is 120 GPa (17.4 Msi).
Thermal5
ZCuAl8Mn13Fe3Ni2-SR is rated for continuous service to 300°C (572 °F). It conducts heat at 12.5 W/m·K (7.22 BTU/hr·ft·°F), worse than 100% of copper alloy grades. Thermal expansion is 16.2 µm/m·K (9 µin/in·°F).
Electrical3
ZCuAl8Mn13Fe3Ni2-SR conducts electricity at 3.2 % IACS, worse than 99% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is very good (78/100), better than 94% of copper alloy grades.
Sustainability4
Producing a kilogram of ZCuAl8Mn13Fe3Ni2-SR takes about 50 MJ of energy and emits 3.5 kg of CO₂ — less than 89% of copper alloy grades. Typical recycled content is 35%.
Manufacturability8
ZCuAl8Mn13Fe3Ni2-SR's machinability is fair (48/100, better than 68% of copper alloy grades); weldability good (65/100); formability poor (22/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with ZCuAl8Mn13Fe3Ni2-SR
Is ZCuAl8Mn13Fe3Ni2 easy to machine?
Machines like a tough duplex bronze (~50 % of free-cutting brass): rigid setup, sharp positive-rake carbide, moderate speed with generous coolant; hard Fe/κ particles abrade tooling.
Can ZCuAl8Mn13Fe3Ni2 be welded?
Weldable by GTAW/GMAW with aluminium-bronze filler (ECuAl-A2 / ERCuNiAl type), 100–200 °C preheat on heavy sections and thorough interpass oxide removal; stress relieve highly restrained repairs.
Can ZCuAl8Mn13Fe3Ni2 be formed, bent or molded?
Casting alloy only — no cold forming; use good gating/filtration to avoid alumina inclusions and control section thickness to limit shrinkage porosity in thick hubs.
What surface finishes work on ZCuAl8Mn13Fe3Ni2?
Not anodizable; grinds and polishes to a bright golden finish, accepts electroless Ni or paint after grit blast; in seawater service leave bare and protect galvanically with Zn/Al anodes when coupled to steel.
ZCuAl8Mn13Fe3Ni2 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 | 7 – 8.5 | 7.8 |
| MnASTM B148 C95700: 11.0–14.0 | 11.5 – 14 | 13 |
| FeASTM B148 C95700: 2.0–4.0 | 2.5 – 4 | 3 |
| NiASTM B148 C95700: 1.5–3.0 | 1.8 – 2.5 | 2 |
| Siimpurity limit | ≤ 0.15 | — |
| Pbimpurity limit | ≤ 0.03 | — |
| Znimpurity limit | ≤ 0.5 | — |
| Snimpurity limit | ≤ 0.2 | — |
| Cu≈71–77 % (remainder) | balance | — |
ZCuAl8Mn13Fe3Ni2-SR — frequently asked
What is ZCuAl8Mn13Fe3Ni2-SR used for?
ZCuAl8Mn13Fe3Ni2-SR is typically used for ship propellers, high-strength structural castings and marine hardware. In short: strongest cast aluminium bronze; propeller-grade toughness; slow to machine.
What is the yield strength of ZCuAl8Mn13Fe3Ni2-SR?
ZCuAl8Mn13Fe3Ni2-SR has a typical yield strength of 300 MPa (43.5 ksi) and a tensile strength of 670 MPa (97.2 ksi) — stronger than 61% of copper alloy grades. Strength varies by condition: see the 5 listed tempers.
Is ZCuAl8Mn13Fe3Ni2-SR easy to machine?
Reasonably — machinability is rated fair (48/100, better than 68% of copper alloy grades). Machines like a tough duplex bronze (~50 % of free-cutting brass): rigid setup, sharp positive-rake carbide, moderate speed with generous coolant; hard Fe/κ particles abrade tooling.
Can ZCuAl8Mn13Fe3Ni2-SR be welded?
Yes — weldability is rated good (65/100). Weldable by GTAW/GMAW with aluminium-bronze filler (ECuAl-A2 / ERCuNiAl type), 100–200 °C preheat on heavy sections and thorough interpass oxide removal; stress relieve highly restrained repairs.
What surface finishes work on ZCuAl8Mn13Fe3Ni2-SR?
Not anodizable; grinds and polishes to a bright golden finish, accepts electroless Ni or paint after grit blast; in seawater service leave bare and protect galvanically with Zn/Al anodes when coupled to steel.
Can ZCuAl8Mn13Fe3Ni2-SR be formed, bent or molded?
Casting alloy only — no cold forming; use good gating/filtration to avoid alumina inclusions and control section thickness to limit shrinkage porosity in thick hubs.
What is the maximum service temperature of ZCuAl8Mn13Fe3Ni2-SR?
ZCuAl8Mn13Fe3Ni2-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 ZCuAl8Mn13Fe3Ni2-S and ZCuAl8Mn13Fe3Ni2-La?
S is the default condition — standard supply condition for propellers, blades and large marine castings of any shape/size. La: best for machined bar and sleeve stock: dense, directionally solidified structure with the highest guaranteed strength. Yield strength is 320 MPa in S versus 345 MPa in La.
Sources
- ASTM B148 — Aluminum-Bronze Sand Castings (C95700) — ASTM (2019)
- ASTM B505/B505M — Continuous Cast Copper Alloys — ASTM (2018)
- CDA Alloy Datasheet C95700 — Copper Development Association (2023)
- ASM Handbook Vol.2 — Properties of Copper Alloys — ASM International (1990)
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.