Stainless Steel S31100 CW-HS
Supply condition
UNS S31100 · AISI/SAE XM-26
CW-HS = cold Worked, high strength
Choose when maximum strength in small sections matters and ductility/toughness can be traded away; not for welded or SCC-critical service.
Values for the CW-HS condition
Other S31100 tempers and conditions
S31100 is listed in 6 conditions; see the grade overview at S31100.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Hot rolled | Thick plate and hot-finished bar for pressure vessels and structural parts where scale/tolerance is machined off. | 490 | 750 | 30 | 22 HRC | 2.2 % IACS |
AnnealedDefault solution annealed and quenched (mill annealed) | Standard supply condition for plate, sheet, bar and pipe; best corrosion resistance and toughness with full duplex phase balance. | 500 | 760 | 30 | 23 HRC | 2.2 % IACS |
As-welded deposit | Reference condition for welded fabrications; expect reduced toughness and pitting resistance unless heat input and filler ferrite balance are controlled. | 500 | 750 | 22 | 24 HRC | 2.2 % IACS |
Cold Rolled + Annealed, 2B finish | Thin sheet and strip for tanks, heat-exchanger and formed components needing a smooth bright surface. | 520 | 780 | 28 | 24 HRC | 2.2 % IACS |
Cold drawn | Cold-drawn bar for shafts, fasteners and machined fittings where tighter tolerance and higher yield are wanted. | 700 | 880 | 20 | 29 HRC | 2.2 % IACS |
CW-HSThis page Cold Worked, high strength | Choose when maximum strength in small sections matters and ductility/toughness can be traded away; not for welded or SCC-critical service. | 830 | 1,000 | 13 | 33 HRC | 2.2 % IACS |
What is S31100 CW-HS?
S31100 CW-HS is S31100 supplied in the CW-HS condition — choose when maximum strength in small sections matters and ductility/toughness can be traded away; not for welded or SCC-critical service. S31100 CW-HS has a yield strength of 830 MPa (120 ksi) and a tensile strength of 1,000 MPa (145 ksi) — stronger than 97% of stainless steel grades. Elongation at break is 13% and the elastic modulus is 200 GPa (29 Msi). S31100 CW-HS has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 65% of stainless steel grades. It melts at 1,400°C (2,552 °F). Annealed is the default condition FabDigit quotes; CW-HS is available on request or by drawing note.
Advantages
- High strength — 830 MPa (120 ksi), better than 97% of stainless steel grades
Limitations
- Limited service temperature — 250°C (482 °F), worse than 99% of stainless steel grades
- Limited ductility — 13%, worse than 93% of stainless steel grades
- Limited formability — 22/100, worse than 82% of stainless steel grades
- Low fracture toughness — 80 MPa·√m (72.8 ksi·√in), worse than 79% of stainless steel grades
- Difficult to weld — 50/100, worse than 77% of stainless steel grades
S31100 CW-HS properties
Typical room-temperature values for S31100 CW-HS; 22 are specific to this condition. Other listed values are S31100 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
S31100 CW-HS has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 65% of stainless steel grades. It melts at 1,400°C (2,552 °F).
Mechanical17
S31100 CW-HS has a yield strength of 830 MPa (120 ksi) and a tensile strength of 1,000 MPa (145 ksi) — stronger than 97% of stainless steel grades. Elongation at break is 13% and the elastic modulus is 200 GPa (29 Msi).
Thermal5
S31100 CW-HS is rated for continuous service to 250°C (482 °F). It conducts heat at 15.5 W/m·K (8.96 BTU/hr·ft·°F), better than 53% of stainless steel grades. Thermal expansion is 13 µm/m·K (7.22 µin/in·°F).
Electrical3
S31100 CW-HS conducts electricity at 2.2 % IACS, worse than 61% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (64/100), better than 54% of stainless steel grades.
Sustainability4
Producing a kilogram of S31100 CW-HS takes about 53 MJ of energy and emits 4.6 kg of CO₂ — less than 67% of stainless steel grades. Typical recycled content is 65%.
Manufacturability8
S31100 CW-HS's machinability is poor (28/100, worse than 79% of stainless steel grades); weldability fair (50/100); formability poor (22/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with S31100 CW-HS
Is S31100 easy to machine?
Machine like 2205: rigid setups, positive-rake carbide, ~30 % of 1212 speeds, heavy feed to cut through the work-hardened skin, flood coolant.
Can S31100 be welded?
GTAW/GMAW/SMAW with 22-9-3 or 25-9-4 over-alloyed filler, no preheat, limited heat input (~0.5–1.5 kJ/mm) and interpass below ~150 °C to keep 40–60 % ferrite; avoid autogenous welds.
Can S31100 be formed, bent or molded?
Cold form with roughly twice the load of 316L and generous springback allowance; hot work 1000–1150 °C followed by solution anneal ~1050 °C and rapid quench.
What surface finishes work on S31100?
Pickle and passivate after welding to restore the passive film; electropolishing or mechanical polishing gives a durable bright finish — no anodizing.
S31100 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 duplex practice | ≤ 0.08 | 0.03 |
| Crconfirm against governing ASTM/UNS listing | 17.5 – 19.5 | 18.5 |
| Ni | 4.5 – 6.5 | 5.5 |
| Mo | 2.5 – 3 | 2.8 |
| Mn | ≤ 2 | 1.2 |
| Si | ≤ 1.5 | 0.6 |
| Naustenite stabiliser, raises pitting resistance | 0.03 – 0.1 | 0.07 |
| P | ≤ 0.04 | — |
| S | ≤ 0.03 | — |
| Fe | balance | — |
S31100 CW-HS — frequently asked
What is S31100 CW-HS used for?
S31100 CW-HS is typically used for chemical process piping, pulp and paper equipment and heat exchangers. In short: moderate-cost lean duplex; better chloride resistance than 316; largely superseded by 2205.
What is the yield strength of S31100 CW-HS?
S31100 CW-HS has a typical yield strength of 830 MPa (120 ksi) and a tensile strength of 1,000 MPa (145 ksi) — stronger than 97% of stainless steel grades. Strength varies by condition: see the 6 listed tempers.
Is S31100 CW-HS easy to machine?
Not especially — machinability is rated poor (28/100, worse than 79% of stainless steel grades). Machine like 2205: rigid setups, positive-rake carbide, ~30 % of 1212 speeds, heavy feed to cut through the work-hardened skin, flood coolant.
Can S31100 CW-HS be welded?
With care — weldability is rated fair (50/100). GTAW/GMAW/SMAW with 22-9-3 or 25-9-4 over-alloyed filler, no preheat, limited heat input (~0.5–1.5 kJ/mm) and interpass below ~150 °C to keep 40–60 % ferrite; avoid autogenous welds.
What surface finishes work on S31100 CW-HS?
Pickle and passivate after welding to restore the passive film; electropolishing or mechanical polishing gives a durable bright finish — no anodizing.
Can S31100 CW-HS be formed, bent or molded?
Cold form with roughly twice the load of 316L and generous springback allowance; hot work 1000–1150 °C followed by solution anneal ~1050 °C and rapid quench.
What is the maximum service temperature of S31100 CW-HS?
S31100 CW-HS is rated for continuous use to about 250°C (482 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between S31100 Annealed and S31100 CW-HS?
Annealed is the default condition — standard supply condition for plate, sheet, bar and pipe; best corrosion resistance and toughness with full duplex phase balance. CW-HS: choose when maximum strength in small sections matters and ductility/toughness can be traded away; not for welded or SCC-critical service. Yield strength is 500 MPa in Annealed versus 830 MPa in CW-HS.
Sources
- ASTM A240/A240M — Chromium and Chromium-Nickel Stainless Steel Plate, Sheet and Strip — ASTM International (2023)
- ASTM A276/A479 — Stainless Steel Bars and Shapes — ASTM International (2022)
- Unified Numbering System for Metals and Alloys (UNS) — SAE/ASTM (2020)
- 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 (2014)
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.