Stainless Steel S44401
UNS S44401
S44401 is a tightened-composition variant close to Type 444 (18Cr-2Mo) ferritic stainless, with Ti/Nb stabilization and lower interstitial carbon and nitrogen for better toughness and corrosion resistance.
Reference datasheet — S44401 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 Annealed condition
S44401 tempers and conditions
S44401 is supplied in 2 conditions, soft to hard. Annealed is the default FabDigit quotes; the values on this page are for it.
Compare all 2 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
AnnealedDefault cold-rolled and annealed sheet/coil (2B finish) | Standard stocked condition for water-heater tanks, tube strip and pressed parts. | 340 | 500 | 30 | 165 HB | — |
Cold drawn | Pick for higher strength and better surface/straightness in fasteners and small tube; ductility and formability drop. | 480 | 590 | 18 | 15 HRC | 2.8 % IACS |
Supply forms, finishes and certifications
Ways S44401 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
Tube-Ann | Welded tube, bright annealed | Supply form |
BA | Bright annealed cold-rolled sheet/strip | Surface finish |
HRAP | Annealed No.1 | Surface finish |
What is S44401?
S44401 is a tightened-composition variant close to Type 444 (18Cr-2Mo) ferritic stainless, with Ti/Nb stabilization and lower interstitial carbon and nitrogen for better toughness and corrosion resistance. Engineers specify it for water-heater and heat-exchanger sheet and tube, available annealed, BA, HRAP, cold-drawn and as annealed tube; annealed values are 340 MPa yield, 500 MPa tensile, 30 % elongation and 165 HB (85 HRB). Continuous service is limited to about 300 °C and formability (68) is below austenitics, so 316L is the usual alternative where deep drawing or higher-temperature service is needed. S44401 has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 65% of stainless steel grades. It melts at 1,425°C (2,597 °F). S44401 has a yield strength of 340 MPa (49.3 ksi) and a tensile strength of 500 MPa (72.5 ksi) — weaker than 55% of stainless steel grades. Elongation at break is 30% and the elastic modulus is 200 GPa (29 Msi).
What is S44401 used for?
- water heater tanks
- heat exchangers
- food equipment
Advantages
- Low embodied carbon — 3.4 kg CO₂/kg, better than 91% of stainless steel grades
- Easy to machine — 45/100, better than 84% of stainless steel grades
- High electrical conductivity — 2.8 % IACS, better than 79% of stainless steel grades
- Conducts heat well — 23 W/m·K (13.3 BTU/hr·ft·°F), better than 78% of stainless steel grades
- Forms and bends easily — 68/100, better than 75% of stainless steel grades
Limitations
- Limited service temperature — 300°C (572 °F), worse than 90% of stainless steel grades
S44401 properties
Typical room-temperature values for S44401-Annealed; bars are the position among stainless steel grades.
Physical3
S44401 has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 65% of stainless steel grades. It melts at 1,425°C (2,597 °F).
Mechanical14
S44401 has a yield strength of 340 MPa (49.3 ksi) and a tensile strength of 500 MPa (72.5 ksi) — weaker than 55% of stainless steel grades. Elongation at break is 30% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
S44401 is rated for continuous service to 300°C (572 °F). It conducts heat at 23 W/m·K (13.3 BTU/hr·ft·°F), better than 78% of stainless steel grades. Thermal expansion is 10.4 µm/m·K (5.78 µin/in·°F).
Electrical3
S44401 conducts electricity at 2.8 % IACS, better than 79% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is very good (72/100), better than 73% of stainless steel grades.
Sustainability4
Producing a kilogram of S44401 takes about 45 MJ of energy and emits 3.4 kg of CO₂ — less than 91% of stainless steel grades. Typical recycled content is 60%.
Manufacturability7
S44401's machinability is fair (45/100, better than 84% of stainless steel grades); weldability very good (72/100); formability good (68/100).
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. S44401 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with S44401
Is S44401 easy to machine?
Machines like a gummy low-carbon ferritic — use sharp positive-rake carbide, rigid setups, generous coolant and moderate speeds with heavy feeds to break the chip.
Can S44401 be welded?
Ti/Nb stabilisation means no post-weld sensitisation, but use low heat input, argon backing and matching 444/316L or Ni-base filler to limit grain coarsening and weld-metal embrittlement.
Can S44401 be formed, bent or molded?
Excellent deep drawability with high r-value and low earing; allow extra springback versus austenitics and avoid severe stretch forming.
S44401 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 interstitial; C+N usually held ≤ 0.04 | ≤ 0.03 | 0.02 |
| Mn | ≤ 1 | 0.4 |
| Si | ≤ 1 | 0.4 |
| P | ≤ 0.04 | 0.03 |
| S | ≤ 0.03 | 0 |
| Cr | 17.5 – 19.5 | 18.5 |
| Ni | ≤ 1 | 0.3 |
| Mo | 1.75 – 2.5 | 2 |
| N | ≤ 0.04 | 0.02 |
| Ti+Nbdual stabilisation, min also expressed as 0.20 + 4(C+N) | 0.2 – 0.8 | 0.4 |
| Fe | balance |
What surface finishes work on S44401?
Pickle and passivate per ASTM A967 after welding; electropolishing or 2B/BA mill finishes give good corrosion performance — no anodising applies.
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 S44401 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Similar grades
- 444
How much does S44401 cost?
S44401 is a standard-cost stainless steel ($$), cheaper than about 71% 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.
S44401 — frequently asked
What is S44401 used for?
S44401 is typically used for water heater tanks, heat exchangers and food equipment. In short: 444-type 18Cr-2Mo ferritic; low-interstitial, tougher weld HAZ; chloride-resistant tank sheet.
What is the yield strength of S44401?
S44401 has a typical yield strength of 340 MPa (49.3 ksi) and a tensile strength of 500 MPa (72.5 ksi) — weaker than 55% of stainless steel grades. Strength varies by condition: see the 2 listed tempers.
Is S44401 easy to machine?
Reasonably — machinability is rated fair (45/100, better than 84% of stainless steel grades). Machines like a gummy low-carbon ferritic — use sharp positive-rake carbide, rigid setups, generous coolant and moderate speeds with heavy feeds to break the chip.
Can S44401 be welded?
Yes — weldability is rated very good (72/100). Ti/Nb stabilisation means no post-weld sensitisation, but use low heat input, argon backing and matching 444/316L or Ni-base filler to limit grain coarsening and weld-metal embrittlement.
What surface finishes work on S44401?
Pickle and passivate per ASTM A967 after welding; electropolishing or 2B/BA mill finishes give good corrosion performance — no anodising applies.
Can S44401 be formed, bent or molded?
Excellent deep drawability with high r-value and low earing; allow extra springback versus austenitics and avoid severe stretch forming.
What is the maximum service temperature of S44401?
S44401 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 S44401 Annealed and S44401-CD?
Annealed is the default condition — standard stocked condition for water-heater tanks, tube strip and pressed parts. CD: pick for higher strength and better surface/straightness in fasteners and small tube; ductility and formability drop. Yield strength is 340 MPa in Annealed versus 480 MPa in CD.
How much does S44401 cost?
S44401 is a standard-cost stainless steel ($$), cheaper than about 71% 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 — ASTM International (2023)
- ASTM A268/A268M — Seamless and Welded Ferritic and Martensitic Stainless Steel Tubing — ASTM International (2022)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- Ferritic stainless 1.4521 / 444 datasheet — Outokumpu (2020)
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.