Stainless Steel S31254 CW-1/2H
Supply condition
UNS S31254 · ASTM A240/A276/A312 · EN 1.4547, X1CrNiMoCuN20-18-7 · JIS SUS890L
CW-1/2H = 1/2 Hard
Highest-strength strip condition offered; only for flat/lightly bent parts, ductility is much reduced.
Values for the CW-1/2H condition
Other S31254 tempers and conditions
S31254 is listed in 5 conditions; see the grade overview at S31254.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Forged + solution annealed | Flanges, valve bodies and heavy fittings; must be re-solution annealed after forging to dissolve intermetallics. | 330 | 670 | 45 | 200 HB | 2 % IACS |
AnnealedDefault solution annealed ~1150–1200 °C + rapid quench (Condition A) | Standard stocked condition for plate, bar, pipe and fittings; maximum corrosion resistance and ductility. | 350 | 680 | 50 | 200 HB | — |
Cold drawn | Pick for shafts, bolting and machined fittings needing higher strength and tight tolerances than annealed bar. | 550 | 800 | 25 | 25 HRC | 2 % IACS |
1/4 Hard | Springy strip/shim and lightly formed parts where extra strength is wanted and corrosion demands stay high. | 620 | 860 | 15 | 28 HRC | 2 % IACS |
CW-1/2HThis page 1/2 Hard | Highest-strength strip condition offered; only for flat/lightly bent parts, ductility is much reduced. | 800 | 1,000 | 10 | 32 HRC | 2 % IACS |
What is S31254 CW-1/2H?
S31254 CW-1/2H is S31254 supplied in the CW-1/2H condition — highest-strength strip condition offered; only for flat/lightly bent parts, ductility is much reduced. S31254 CW-1/2H has a yield strength of 800 MPa (116 ksi) and a tensile strength of 1,000 MPa (145 ksi) — stronger than 96% of stainless steel grades. Elongation at break is 10% and the elastic modulus is 193 GPa (28 Msi). S31254 CW-1/2H has a density of 8 g/cm³ (0.289 lb/in³), heavier than 92% of stainless steel grades. It melts at 1,325°C (2,417 °F). Annealed is the default condition FabDigit quotes; CW-1/2H is available on request or by drawing note.
Advantages
- High strength — 800 MPa (116 ksi), better than 96% of stainless steel grades
- Good corrosion resistance — 85/100, better than 92% of stainless steel grades
- Polishes to a fine finish — 80/100, better than 89% of stainless steel grades
Limitations
- Limited ductility — 10%, worse than 98% of stainless steel grades
- Difficult to machine — 20/100, worse than 98% of stainless steel grades
- Limited service temperature — 300°C (572 °F), worse than 90% of stainless steel grades
- High embodied carbon — 6.2 kg CO₂/kg, worse than 90% of stainless steel grades
- Limited formability — 20/100, worse than 86% of stainless steel grades
S31254 CW-1/2H properties
Typical room-temperature values for S31254 CW-1/2H; 24 are specific to this condition. Other listed values are S31254 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
S31254 CW-1/2H has a density of 8 g/cm³ (0.289 lb/in³), heavier than 92% of stainless steel grades. It melts at 1,325°C (2,417 °F).
Mechanical15
S31254 CW-1/2H has a yield strength of 800 MPa (116 ksi) and a tensile strength of 1,000 MPa (145 ksi) — stronger than 96% of stainless steel grades. Elongation at break is 10% and the elastic modulus is 193 GPa (28 Msi).
Thermal6
S31254 CW-1/2H is rated for continuous service to 300°C (572 °F). It conducts heat at 14 W/m·K (8.09 BTU/hr·ft·°F), worse than 80% of stainless steel grades. Thermal expansion is 16.5 µm/m·K (9.17 µin/in·°F).
Electrical3
S31254 CW-1/2H conducts electricity at 2 % IACS, worse than 77% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is excellent (85/100), better than 92% of stainless steel grades.
Sustainability4
Producing a kilogram of S31254 CW-1/2H takes about 90 MJ of energy and emits 6.2 kg of CO₂ — more than 94% of stainless steel grades. Typical recycled content is 45%.
Manufacturability7
S31254 CW-1/2H's machinability is poor (20/100, worse than 98% of stainless steel grades); weldability good (60/100); formability poor (20/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with S31254 CW-1/2H
Is S31254 easy to machine?
Machines like a heavily work-hardening austenitic: use rigid setups, positive-rake sharp carbide, low speed with heavy feed, generous flood coolant, and never let the tool dwell — expect roughly 30% of 1212 rates.
Can S31254 be welded?
GTAW/GMAW/SMAW with over-alloyed Ni-base filler (ERNiCrMo-3 / 625 type) to keep weld-metal PREN up; low heat input, no preheat, interpass below ~150 °C, and post-weld pickling of heat tint.
Can S31254 be formed, bent or molded?
Cold forms well but needs ~2× the press force of 304 and generous springback allowance; hot work 1150–1200 °C and always solution anneal and quench afterwards.
What surface finishes work on S31254?
Pickle/passivate or electropolish to restore the chloride-resistant passive film; grind out heat tint and embedded iron, do not anodize.
S31254 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 sensitization | ≤ 0.02 | 0.01 |
| Si | ≤ 0.8 | 0.4 |
| Mn | ≤ 1 | 0.6 |
| P | ≤ 0.03 | — |
| S | ≤ 0.01 | — |
| Cr | 19.5 – 20.5 | 20 |
| Ni | 17.5 – 18.5 | 18 |
| Mo6Mo grade, drives PREN ≈ 43 | 6 – 6.5 | 6.2 |
| Cuimproves resistance in reducing acids | 0.5 – 1 | 0.7 |
| Naustenite stabilizer, boosts strength and pitting resistance | 0.18 – 0.25 | 0.2 |
| Fe | balance | — |
S31254 CW-1/2H — frequently asked
What is S31254 CW-1/2H used for?
S31254 CW-1/2H is typically used for seawater piping and heat exchangers, desalination equipment, pulp and paper bleaching plants, flue gas desulfurization systems and offshore and marine hardware. In short: seawater-grade 6% Mo stainless; PRE around 43; upgrade from 316L/904L.
What is the yield strength of S31254 CW-1/2H?
S31254 CW-1/2H has a typical yield strength of 800 MPa (116 ksi) and a tensile strength of 1,000 MPa (145 ksi) — stronger than 96% of stainless steel grades. Strength varies by condition: see the 5 listed tempers.
Is S31254 CW-1/2H easy to machine?
Not especially — machinability is rated poor (20/100, worse than 98% of stainless steel grades). Machines like a heavily work-hardening austenitic: use rigid setups, positive-rake sharp carbide, low speed with heavy feed, generous flood coolant, and never let the tool dwell — expect roughly 30% of 1212 rates.
Can S31254 CW-1/2H be welded?
Yes — weldability is rated good (60/100). GTAW/GMAW/SMAW with over-alloyed Ni-base filler (ERNiCrMo-3 / 625 type) to keep weld-metal PREN up; low heat input, no preheat, interpass below ~150 °C, and post-weld pickling of heat tint.
What surface finishes work on S31254 CW-1/2H?
Pickle/passivate or electropolish to restore the chloride-resistant passive film; grind out heat tint and embedded iron, do not anodize.
Can S31254 CW-1/2H be formed, bent or molded?
Cold forms well but needs ~2× the press force of 304 and generous springback allowance; hot work 1150–1200 °C and always solution anneal and quench afterwards.
What is the maximum service temperature of S31254 CW-1/2H?
S31254 CW-1/2H 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 S31254 Annealed and S31254-CD?
Annealed is the default condition — standard stocked condition for plate, bar, pipe and fittings; maximum corrosion resistance and ductility. CD: pick for shafts, bolting and machined fittings needing higher strength and tight tolerances than annealed bar. Yield strength is 350 MPa in Annealed versus 550 MPa in CD.
Sources
- ASTM A240/A240M — Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip — ASTM International (2023)
- ASTM A312/A276/A479/A182 (F44) — pipe, bar and forging specifications — ASTM International (2022)
- EN 10088-2 — Stainless steels: sheet/plate, grade 1.4547 (X1CrNiMoCuN20-18-7) — CEN (2014)
- 254 SMO / S31254 alloy datasheet (physical, mechanical and corrosion data) — Outokumpu (2023)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels, and High-Performance 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.