Nickel Alloy CW-12MW-SA (Solution annealed)
Heat-treated state · default condition
UNS N30002, J30002 · ASTM A494 CW12MW
Standard supply condition for A494 CW-12MW corrosion castings — carbides dissolved, maximum corrosion resistance and ductility.
Values for the SA condition
Other CW-12MW tempers and conditions
CW-12MW is listed in 4 conditions; see the grade overview at CW-12MW.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
As fabricated | Only for non-critical, low-corrosivity duty or parts to be heat treated later; interdendritic carbides reduce ductility and intergranular corrosion resistance. | 340 | 500 | 4 | 18 HRC | 1.4 % IACS |
As-welded deposit | Condition of weld-repaired areas before re-solution annealing; acceptable for mild service but sensitised HAZ limits acid duty. | 345 | 520 | 6 | 17 HRC | 1.4 % IACS |
SADefaultThis page Solution annealed | Standard supply condition for A494 CW-12MW corrosion castings — carbides dissolved, maximum corrosion resistance and ductility. | 350 | 550 | 10 | 15 HRC | — |
hot isostatically pressed then solution annealed | For pressure-boundary or high-integrity castings where internal microporosity must be closed; slightly higher ductility and fatigue life. | 360 | 575 | 15 | 15 HRC | 1.3 % IACS |
What is CW-12MW-SA?
CW-12MW-SA is CW-12MW heat treated to SA — standard supply condition for A494 CW-12MW corrosion castings — carbides dissolved, maximum corrosion resistance and ductility. CW-12MW-SA has a yield strength of 350 MPa (50.8 ksi) and a tensile strength of 550 MPa (79.8 ksi) — weaker than 60% of nickel alloy grades. Elongation at break is 10% and the elastic modulus is 205 GPa (29.7 Msi). CW-12MW-SA has a density of 8.94 g/cm³ (0.323 lb/in³), heavier than 92% of nickel alloy grades. It melts at 1,275°C (2,327 °F).
Limitations
- Limited ductility — 10%, worse than 85% of nickel alloy grades
- Limited formability — 15/100, worse than 81% of nickel alloy grades
CW-12MW-SA properties
Typical room-temperature values for CW-12MW-SA; 11 are specific to this condition. Other listed values are CW-12MW reference data and may not represent this condition. Bars are the position among nickel alloy grades.
Physical3
CW-12MW-SA has a density of 8.94 g/cm³ (0.323 lb/in³), heavier than 92% of nickel alloy grades. It melts at 1,275°C (2,327 °F).
Mechanical14
CW-12MW-SA has a yield strength of 350 MPa (50.8 ksi) and a tensile strength of 550 MPa (79.8 ksi) — weaker than 60% of nickel alloy grades. Elongation at break is 10% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
CW-12MW-SA is rated for continuous service to 650°C (1,202 °F). It conducts heat at 10.2 W/m·K (5.89 BTU/hr·ft·°F), worse than 79% of nickel alloy grades. Thermal expansion is 11.3 µm/m·K (6.28 µin/in·°F).
Electrical3
CW-12MW-SA conducts electricity at 1.3 % IACS, worse than 89% of nickel alloy grades.
Chemical & Environmental3
Corrosion resistance is excellent (86/100), better than 77% of nickel alloy grades.
Sustainability4
Producing a kilogram of CW-12MW-SA takes about 150 MJ of energy and emits 12.5 kg of CO₂ — less than 68% of nickel alloy grades. Typical recycled content is 40%.
Manufacturability8
CW-12MW-SA's machinability is poor (22/100, better than 64% of nickel alloy grades); weldability good (55/100); formability poor (15/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with CW-12MW-SA
Is CW-12MW easy to machine?
Very gummy and work-hardening — use rigid setups, positive-rake carbide or ceramic inserts, low speed (15–25 m/min carbide), heavy positive feed, flood coolant, and never dwell in the cut.
Can CW-12MW be welded?
GTAW/SMAW with matching ERNiCrMo-5 (or ENiCrMo-5) filler, low heat input, no preheat, interpass < 100 °C; re-solution anneal and quench after major weld repair to restore corrosion resistance.
Can CW-12MW be formed, bent or molded?
Casting grade only — sand or investment cast with generous risering (wide freezing range, high shrinkage ~2.2 %); solution anneal after shakeout, machine allowances should account for hard skin.
What surface finishes work on CW-12MW?
Grit blast, pickle in HNO3–HF then passivate; electropolish or mechanically polish sealing faces; no anodising — apply no coating in acid service so the natural passive film works.
CW-12MW 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 |
|---|---|---|
| Chigher than wrought C-276 | ≤ 0.12 | 0.08 |
| Mn | ≤ 1 | 0.6 |
| Si | ≤ 1 | 0.7 |
| P | ≤ 0.04 | — |
| S | ≤ 0.03 | — |
| Cr | 15.5 – 17.5 | 16.5 |
| Mo | 16 – 18 | 17 |
| W | 3.75 – 5.25 | 4.5 |
| Fe | 4.5 – 7.5 | 6 |
| V | 0.2 – 0.4 | 0.3 |
| Nibalance, nominally ~54 % | balance | — |
CW-12MW-SA — frequently asked
What is CW-12MW-SA used for?
CW-12MW-SA is typically used for chemical process pumps, acid valve bodies and flue gas equipment castings. In short: cast Hastelloy C; best cast corrosion resistance; mixed-acid casting grade.
What is the yield strength of CW-12MW-SA?
CW-12MW-SA has a typical yield strength of 350 MPa (50.8 ksi) and a tensile strength of 550 MPa (79.8 ksi) — weaker than 60% of nickel alloy grades. Strength varies by condition: see the 4 listed tempers.
Is CW-12MW-SA easy to machine?
Not especially — machinability is rated poor (22/100, better than 64% of nickel alloy grades). Very gummy and work-hardening — use rigid setups, positive-rake carbide or ceramic inserts, low speed (15–25 m/min carbide), heavy positive feed, flood coolant, and never dwell in the cut.
Can CW-12MW-SA be welded?
Yes — weldability is rated good (55/100). GTAW/SMAW with matching ERNiCrMo-5 (or ENiCrMo-5) filler, low heat input, no preheat, interpass < 100 °C; re-solution anneal and quench after major weld repair to restore corrosion resistance.
What surface finishes work on CW-12MW-SA?
Grit blast, pickle in HNO3–HF then passivate; electropolish or mechanically polish sealing faces; no anodising — apply no coating in acid service so the natural passive film works.
Can CW-12MW-SA be formed, bent or molded?
Casting grade only — sand or investment cast with generous risering (wide freezing range, high shrinkage ~2.2 %); solution anneal after shakeout, machine allowances should account for hard skin.
What is the maximum service temperature of CW-12MW-SA?
CW-12MW-SA is rated for continuous use to about 650°C (1,202 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between CW-12MW-SA and CW-12MW-F?
SA is the default condition — standard supply condition for A494 CW-12MW corrosion castings — carbides dissolved, maximum corrosion resistance and ductility. F: only for non-critical, low-corrosivity duty or parts to be heat treated later; interdendritic carbides reduce ductility and intergranular corrosion resistance. Yield strength is 350 MPa in SA versus 340 MPa in F.
Sources
- ASTM A494/A494M — Castings, Nickel and Nickel Alloy — ASTM International (2023)
- ASM Specialty Handbook: Nickel, Cobalt, and Their Alloys — ASM International (2000)
- ASM Handbook Vol.15 — Casting — ASM International (2008)
- Hastelloy C-type alloy physical and corrosion data — Haynes International (2020)
- UNS N30002 / J30002 alloy record — SAE/ASTM Unified Numbering System (2019)
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.