Stainless Steel S33228
UNS S33228 · ASTM A240
S33228 is a niobium-stabilized, nitrogen-strengthened high Cr-Ni austenitic stainless supplied to ASTM A240 for elevated-temperature service up to 1100 °C.
Reference datasheet — S33228 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the SA condition
S33228 tempers and conditions
S33228 is supplied in 3 conditions, soft to hard. SA is the default FabDigit quotes; the values on this page are for it.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
SADefault Solution annealed | Standard supply condition for all product forms; maximum ductility, homogeneous carbide/Nb distribution before high-temperature service. | 280 | 620 | 42 | 170 HB | — |
Cold drawn / cold pilgered and bright solution annealed tube and bar | Seamless tube, pipe and bar condition for reformer/pyrolysis tubing and machined furnace components; tight tolerance and bright surface. | 290 | 630 | 40 | 172 HB | 1.7 % IACS |
Cold worked | Occasional strip condition where extra room-temperature stiffness/spring-back is needed; the cold work is lost on first exposure above ~700 °C. | 520 | 780 | 20 | 21 HRC | 1.7 % IACS |
Supply forms, finishes and certifications
Ways S33228 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
CRA-2B | CRA 2B | Surface finish |
HRAP | Hot rolled, solution annealed and pickled plate | Surface finish |
What is S33228?
S33228 is a niobium-stabilized, nitrogen-strengthened high Cr-Ni austenitic stainless supplied to ASTM A240 for elevated-temperature service up to 1100 °C. Annealed material gives 280 MPa yield, 620 MPa tensile, 42 % elongation and about 170 HB as plate, hot- and cold-rolled annealed sheet, and cold-drawn or cold-worked bar. Its localized-corrosion rating (score 55) is well below chloride-optimized superaustenitics such as S31254, machinability is low (score 25), and heavily restrained sections can suffer reheat cracking above 600 °C. S33228 has a density of 7.9 g/cm³ (0.285 lb/in³), heavier than 68% of stainless steel grades. It melts at 1,340°C (2,444 °F). S33228 has a yield strength of 280 MPa (40.6 ksi) and a tensile strength of 620 MPa (89.9 ksi) — weaker than 75% of stainless steel grades. Elongation at break is 42% and the elastic modulus is 190 GPa (27.6 Msi).
What is S33228 used for?
- chemical process equipment
- marine components
- high-strength corrosion-resistant fasteners
- pollution control systems
Advantages
- High service temperature — 1,100°C (2,012 °F), better than 96% of stainless steel grades
Limitations
- Poor heat conductor — 11.5 W/m·K (6.64 BTU/hr·ft·°F), worse than 97% of stainless steel grades
- High embodied carbon — 7 kg CO₂/kg, worse than 96% of stainless steel grades
- Low electrical conductivity — 1.7 % IACS, worse than 93% of stainless steel grades
- Difficult to machine — 25/100, worse than 88% of stainless steel grades
- Low strength — 280 MPa (40.6 ksi), worse than 75% of stainless steel grades
S33228 properties
Typical room-temperature values for S33228-SA; bars are the position among stainless steel grades.
Physical3
S33228 has a density of 7.9 g/cm³ (0.285 lb/in³), heavier than 68% of stainless steel grades. It melts at 1,340°C (2,444 °F).
Mechanical14
S33228 has a yield strength of 280 MPa (40.6 ksi) and a tensile strength of 620 MPa (89.9 ksi) — weaker than 75% of stainless steel grades. Elongation at break is 42% and the elastic modulus is 190 GPa (27.6 Msi).
Thermal6
S33228 is rated for continuous service to 1,100°C (2,012 °F). It conducts heat at 11.5 W/m·K (6.64 BTU/hr·ft·°F), worse than 97% of stainless steel grades. Thermal expansion is 15 µm/m·K (8.33 µin/in·°F).
Electrical3
S33228 conducts electricity at 1.7 % IACS, worse than 93% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (55/100), worse than 71% of stainless steel grades.
Sustainability4
Producing a kilogram of S33228 takes about 90 MJ of energy and emits 7 kg of CO₂ — more than 94% of stainless steel grades. Typical recycled content is 40%.
Manufacturability7
S33228's machinability is poor (25/100, worse than 88% of stainless steel grades); weldability good (65/100); formability good (60/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the stainless steel family
Yield strength against density for every stainless steel grade FabDigit runs. S33228 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with S33228
Is S33228 easy to machine?
Machine like 310S/800H: rigid setups, positive-rake carbide, low speed and heavy positive feed to stay under the work-hardened layer, flood coolant, avoid dwelling.
Can S33228 be welded?
GTAW/GMAW/SMAW with matching Nb-stabilized or Ni-base (ERNiCr-3 / alloy 617 type) filler; low heat input, interpass <150 °C, no preheat, no post-weld heat treatment normally required — but avoid restraint in heavy sections because of reheat (relaxation) cracking above 600 °C.
Can S33228 be formed, bent or molded?
Cold forms well but work-hardens fast — allow ~50% more press force than 304 and intermediate anneals at 1150–1200 °C with rapid cooling; hot work 1150–1200 °C, stop above 950 °C.
S33228 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 |
|---|---|---|
| C | 0.04 – 0.08 | 0.06 |
| Mn | ≤ 1 | 0.6 |
| Si | ≤ 0.3 | 0.2 |
| P | ≤ 0.02 | |
| S | ≤ 0.02 | |
| Cr | 26 – 28 | 27 |
| Ni | 31 – 33 | 32 |
| Nbcarbide stabilization / creep strength | 0.6 – 1 | 0.8 |
| Cerare earth for oxide-scale adhesion | 0.05 – 0.1 | 0.07 |
| Al | ≤ 0.03 | |
| Tiresidual limit | ≤ 0.05 | |
| Febalance ≈38–41 % | balance |
What surface finishes work on S33228?
Pickle in HNO₃-HF after hot work or welding to restore the Cr₂O₃-forming surface; mechanical grinding/polishing must use iron-free media, and no anodizing applies to this alloy class.
Surface treatments FabDigit runs on stainless steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Passivation
Organic Coating
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Stainless Steel S33228 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- A240
How much does S33228 cost?
S33228 is a high-cost stainless steel ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
S33228 — frequently asked
What is S33228 used for?
S33228 is typically used for chemical process equipment, marine components, high-strength corrosion-resistant fasteners and pollution control systems. In short: 1100 °C service ceiling; nb-stabilized against sensitization; moderate chloride resistance only.
What is the yield strength of S33228?
S33228 has a typical yield strength of 280 MPa (40.6 ksi) and a tensile strength of 620 MPa (89.9 ksi) — weaker than 75% of stainless steel grades. Strength varies by condition: see the 3 listed tempers.
Is S33228 easy to machine?
Not especially — machinability is rated poor (25/100, worse than 88% of stainless steel grades). Machine like 310S/800H: rigid setups, positive-rake carbide, low speed and heavy positive feed to stay under the work-hardened layer, flood coolant, avoid dwelling.
Can S33228 be welded?
Yes — weldability is rated good (65/100). GTAW/GMAW/SMAW with matching Nb-stabilized or Ni-base (ERNiCr-3 / alloy 617 type) filler; low heat input, interpass <150 °C, no preheat, no post-weld heat treatment normally required — but avoid restraint in heavy sections because of reheat (relaxation) cracking above 600 °C.
What surface finishes work on S33228?
Pickle in HNO₃-HF after hot work or welding to restore the Cr₂O₃-forming surface; mechanical grinding/polishing must use iron-free media, and no anodizing applies to this alloy class.
Can S33228 be formed, bent or molded?
Cold forms well but work-hardens fast — allow ~50% more press force than 304 and intermediate anneals at 1150–1200 °C with rapid cooling; hot work 1150–1200 °C, stop above 950 °C.
What is the maximum service temperature of S33228?
S33228 is rated for continuous use to about 1,100°C (2,012 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between S33228-SA and S33228-CW?
SA is the default condition — standard supply condition for all product forms; maximum ductility, homogeneous carbide/Nb distribution before high-temperature service. CW: occasional strip condition where extra room-temperature stiffness/spring-back is needed; the cold work is lost on first exposure above ~700 °C. Yield strength is 280 MPa in SA versus 520 MPa in CW.
How much does S33228 cost?
S33228 is a high-cost stainless steel ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- ASTM A240/A240M — Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip (UNS S33228) — ASTM International (2023)
- EN 10095 — Heat resisting steels and nickel alloys (X8CrNiNbCe32-27, 1.4877) — CEN (1999)
- Nicrofer 3228 NbCe / alloy 803-type heat resistant austenitic alloy data sheet — VDM Metals (2018)
- ASM Handbook Vol.1 — Heat-Resistant Austenitic Stainless Steels — ASM International (1990)
- ASM Handbook Vol.13B — Corrosion: High-Temperature Corrosion of Fe-Ni-Cr Alloys — ASM International (2005)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.