Stainless Steel CD3MWCuN-SA
Heat-treated state · default condition
ASTM CD3MWCuN · UNS J93380
SA = solution annealed 1100–1180 °C, water quenched
Standard and essentially only commercial delivery condition for CD3MWCuN castings; gives balanced ferrite/austenite, full corrosion resistance and code-compliant properties.
Values for the SA condition
Other CD3MWCuN tempers and conditions
CD3MWCuN is listed in 4 conditions; see the grade overview at CD3MWCuN.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Spheroidize annealed | Only an intermediate shop condition: as-cast structure contains sigma/intermetallics and nitrides, so strength scatter is wide and corrosion/toughness are unacceptable — always solution treat before service. | 500 | 700 | 12 | 28 HRC | 2 % IACS |
SADefaultThis page Solution annealed 1100–1180 °C, water quenched | Standard and essentially only commercial delivery condition for CD3MWCuN castings; gives balanced ferrite/austenite, full corrosion resistance and code-compliant properties. | 530 | 780 | 32 | 24 HRC | — |
Hot isostatically pressed then solution annealed and quenched | Choose for thick-section, pressure-containing or NDE-critical castings where HIP closes internal microporosity and lifts ductility and toughness. | 545 | 800 | 36 | 25 HRC | 2 % IACS |
Centrifugally cast tube/ring, solution annealed and quenched | Pick for seawater piping spools, sleeves and rings where the fine, dense centrifugal structure gives slightly higher strength and better soundness than static castings. | 560 | 810 | 30 | 25 HRC | 2 % IACS |
What is CD3MWCuN-SA?
CD3MWCuN-SA is CD3MWCuN heat treated to SA — standard and essentially only commercial delivery condition for CD3MWCuN castings; gives balanced ferrite/austenite, full corrosion resistance and code-compliant properties. CD3MWCuN-SA has a yield strength of 530 MPa (76.9 ksi) and a tensile strength of 780 MPa (113 ksi) — stronger than 81% of stainless steel grades. Elongation at break is 32% and the elastic modulus is 200 GPa (29 Msi). CD3MWCuN-SA has a density of 7.8 g/cm³ (0.282 lb/in³), heavier than 50% of stainless steel grades. It melts at 1,350°C (2,462 °F).
Advantages
- Good corrosion resistance — 86/100, better than 94% of stainless steel grades
- High strength — 530 MPa (76.9 ksi), better than 81% of stainless steel grades
Limitations
- Limited service temperature — 280°C (536 °F), worse than 96% of stainless steel grades
- Limited formability — 20/100, worse than 86% of stainless steel grades
- Low electrical conductivity — 2 % IACS, worse than 77% of stainless steel grades
- High embodied carbon — 5.5 kg CO₂/kg, worse than 77% of stainless steel grades
CD3MWCuN-SA properties
Typical room-temperature values for CD3MWCuN-SA; 14 are specific to this condition. Other listed values are CD3MWCuN reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
CD3MWCuN-SA has a density of 7.8 g/cm³ (0.282 lb/in³), heavier than 50% of stainless steel grades. It melts at 1,350°C (2,462 °F).
Mechanical16
CD3MWCuN-SA has a yield strength of 530 MPa (76.9 ksi) and a tensile strength of 780 MPa (113 ksi) — stronger than 81% of stainless steel grades. Elongation at break is 32% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
CD3MWCuN-SA is rated for continuous service to 280°C (536 °F). It conducts heat at 14.2 W/m·K (8.2 BTU/hr·ft·°F), worse than 76% of stainless steel grades. Thermal expansion is 12.8 µm/m·K (7.11 µin/in·°F).
Electrical3
CD3MWCuN-SA conducts electricity at 2 % IACS, worse than 77% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is excellent (86/100), better than 94% of stainless steel grades.
Sustainability4
Producing a kilogram of CD3MWCuN-SA takes about 60 MJ of energy and emits 5.5 kg of CO₂ — more than 70% of stainless steel grades. Typical recycled content is 60%.
Manufacturability8
CD3MWCuN-SA's machinability is poor (28/100, worse than 79% of stainless steel grades); weldability good (60/100); formability poor (20/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with CD3MWCuN-SA
Is CD3MWCuN easy to machine?
Work-hardens strongly and cuts hard — use rigid setups, sharp coated carbide, low speed / high feed, generous flood coolant and avoid dwelling to prevent glazing.
Can CD3MWCuN be welded?
Readily weldable with GTAW/SMAW using over-alloyed 25.10.4L (Zeron 100X) filler, N₂-bearing Ar shielding, interpass ≤150 °C and controlled heat input to keep ferrite 35–55 %; no PWHT, re-solution treat only if intermetallics are suspected.
Can CD3MWCuN be formed, bent or molded?
Sand or centrifugal casting with ~2.0–2.3 % shrinkage allowance; feed heavy sections well and quench from 1100–1180 °C fast enough to suppress sigma phase in thick walls.
What surface finishes work on CD3MWCuN?
Grit blast, pickle in HNO₃/HF and passivate per ASTM A967 to restore the passive film; electropolishing gives the best seawater performance — no anodizing.
CD3MWCuN 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 |
|---|---|---|
| Clow carbon to avoid carbide sensitisation | ≤ 0.03 | 0.02 |
| Cr | 24 – 26 | 25 |
| Ni | 6.5 – 8.5 | 7.5 |
| Mo | 3 – 4 | 3.5 |
| Cu | 0.5 – 1 | 0.75 |
| Wtungsten raises crevice-corrosion resistance | 0.5 – 1 | 0.75 |
| Naustenite stabiliser, PREN contributor | 0.2 – 0.3 | 0.25 |
| Mn | ≤ 1 | 0.7 |
| Si | ≤ 1 | 0.6 |
| P | ≤ 0.03 | 0.02 |
| S | ≤ 0.03 | 0.01 |
| Febalance; PREN = Cr + 3.3(Mo + 0.5W) + 16N ≈ 40–42 | balance | — |
CD3MWCuN-SA — frequently asked
What is CD3MWCuN-SA used for?
CD3MWCuN-SA is typically used for subsea valve bodies, offshore pump casings, seawater injection equipment and high-pressure fittings. In short: cast super duplex; seawater-grade castings; NORSOK-qualified chemistry.
What is the yield strength of CD3MWCuN-SA?
CD3MWCuN-SA has a typical yield strength of 530 MPa (76.9 ksi) and a tensile strength of 780 MPa (113 ksi) — stronger than 81% of stainless steel grades. Strength varies by condition: see the 4 listed tempers.
Is CD3MWCuN-SA easy to machine?
Not especially — machinability is rated poor (28/100, worse than 79% of stainless steel grades). Work-hardens strongly and cuts hard — use rigid setups, sharp coated carbide, low speed / high feed, generous flood coolant and avoid dwelling to prevent glazing.
Can CD3MWCuN-SA be welded?
Yes — weldability is rated good (60/100). Readily weldable with GTAW/SMAW using over-alloyed 25.10.4L (Zeron 100X) filler, N₂-bearing Ar shielding, interpass ≤150 °C and controlled heat input to keep ferrite 35–55 %; no PWHT, re-solution treat only if intermetallics are suspected.
What surface finishes work on CD3MWCuN-SA?
Grit blast, pickle in HNO₃/HF and passivate per ASTM A967 to restore the passive film; electropolishing gives the best seawater performance — no anodizing.
Can CD3MWCuN-SA be formed, bent or molded?
Sand or centrifugal casting with ~2.0–2.3 % shrinkage allowance; feed heavy sections well and quench from 1100–1180 °C fast enough to suppress sigma phase in thick walls.
What is the maximum service temperature of CD3MWCuN-SA?
CD3MWCuN-SA is rated for continuous use to about 280°C (536 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between CD3MWCuN-SA and CD3MWCuN-AC?
SA is the default condition — standard and essentially only commercial delivery condition for CD3MWCuN castings; gives balanced ferrite/austenite, full corrosion resistance and code-compliant properties. AC: only an intermediate shop condition: as-cast structure contains sigma/intermetallics and nitrides, so strength scatter is wide and corrosion/toughness are unacceptable — always solution treat before service. Yield strength is 530 MPa in SA versus 500 MPa in AC.
Sources
- ASTM A995/A995M — Castings, Austenitic-Ferritic (Duplex) Stainless Steel, for Pressure-Containing Parts — ASTM International (2020)
- ASTM A890/A890M — Castings, Iron-Chromium-Nickel-Molybdenum Corrosion-Resistant, Duplex — ASTM International (2023)
- ASTM A923 — Detecting Detrimental Intermetallic Phase in Duplex Austenitic/Ferritic Stainless Steels — ASTM International (2022)
- EN 10283 / EN 10213 (1.4469 GX2CrNiMoCuN25-6-3-3 class castings) — CEN (2010)
- Zeron 100 super duplex stainless steel data sheet — Rolled Alloys / Neonickel (2021)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- Practical Guidelines for the Fabrication of Duplex Stainless Steels — IMOA / International Molybdenum Association (2014)
- NORSOK M-630 Material Data Sheets (duplex castings) — Standards Norway (2021)
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.