Stainless Steel S44800 As Welded
Finish state
UNS S44800
Reference condition for fabricated joints: strength is retained but HAZ grain coarsening lowers toughness.
Values for the As Welded condition
Other S44800 tempers and conditions
S44800 is listed in 3 conditions; see the grade overview at S44800.
- As Welded
- Annealed
- Cold Worked
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
As WeldedThis page As-welded (autogenous GTAW, no post-weld anneal) | Reference condition for fabricated joints: strength is retained but HAZ grain coarsening lowers toughness. | 470 | 610 | 15 | 17 HRC | 2.3 % IACS |
AnnealedDefault mill annealed, pickled (plate/sheet/strip) | Standard stocked condition for all forming, welding and corrosion service; best ductility and toughness. | 480 | 620 | 25 | 210 HB | — |
Cold worked (as-rolled / temper rolled strip, not annealed) | Special order only — higher strength springy strip, at the cost of ductility and notch toughness. | 700 | 800 | 6 | 28 HRC | 2.2 % IACS |
What is S44800 As Welded?
S44800 As Welded is S44800 supplied in the As Welded condition — reference condition for fabricated joints: strength is retained but HAZ grain coarsening lowers toughness. S44800 As Welded has a yield strength of 470 MPa (68.2 ksi) and a tensile strength of 610 MPa (88.5 ksi) — stronger than 74% of stainless steel grades. Elongation at break is 15% and the elastic modulus is 200 GPa (29 Msi). S44800 As Welded has a density of 7.67 g/cm³ (0.277 lb/in³), lighter than 95% of stainless steel grades. It melts at 1,420°C (2,588 °F). Annealed is the default condition FabDigit quotes; As Welded is available on request or by drawing note.
Advantages
- Good corrosion resistance — 84/100, better than 91% of stainless steel grades
Limitations
- Limited service temperature — 300°C (572 °F), worse than 90% of stainless steel grades
- Limited ductility — 15%, worse than 89% of stainless steel grades
- Difficult to weld — 50/100, worse than 77% of stainless steel grades
S44800 As Welded properties
Typical room-temperature values for S44800 As Welded; 23 are specific to this condition. Other listed values are S44800 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
S44800 As Welded has a density of 7.67 g/cm³ (0.277 lb/in³), lighter than 95% of stainless steel grades. It melts at 1,420°C (2,588 °F).
Mechanical15
S44800 As Welded has a yield strength of 470 MPa (68.2 ksi) and a tensile strength of 610 MPa (88.5 ksi) — stronger than 74% of stainless steel grades. Elongation at break is 15% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
S44800 As Welded is rated for continuous service to 300°C (572 °F). It conducts heat at 16 W/m·K (9.24 BTU/hr·ft·°F), better than 58% of stainless steel grades. Thermal expansion is 10.4 µm/m·K (5.78 µin/in·°F).
Electrical3
S44800 As Welded conducts electricity at 2.3 % IACS, better than 55% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is very good (84/100), better than 91% of stainless steel grades.
Sustainability4
Producing a kilogram of S44800 As Welded takes about 70 MJ of energy and emits 5.2 kg of CO₂ — more than 81% of stainless steel grades. Typical recycled content is 30%.
Manufacturability7
S44800 As Welded's machinability is poor (33/100, worse than 57% of stainless steel grades); weldability fair (50/100); formability fair (35/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with S44800 As Welded
Is S44800 easy to machine?
Machines like a tough ferritic stainless (~40% of 1212): rigid setups, sharp positive-rake carbide, heavy feeds and flood coolant to avoid work-hardened glazing and built-up edge.
Can S44800 be welded?
Weld autogenously by GTAW/PAW with very high-purity argon (trailing and backing gas), low heat input and scrupulous cleanliness; carbon, nitrogen or oxygen pickup embrittles the weld — avoid austenitic fillers where matching corrosion resistance is required, and never preheat above ~150 °C.
Can S44800 be formed, bent or molded?
Cold forms well for a super-ferritic in thin gauge (roll forming, tube making, moderate draws); use generous bend radii, expect higher springback than 304 and warm form ~150–250 °C for severe bends in heavier sections.
What surface finishes work on S44800?
Pickle and passivate after hot work or welding to restore the Cr-Mo oxide film; electropolishing or mechanical polishing gives excellent seawater-service surfaces — no anodizing.
S44800 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 |
|---|---|---|
| CC+N ≤ 0.025% | ≤ 0.01 | 0.01 |
| NC+N ≤ 0.025% | ≤ 0.02 | 0.01 |
| Cr | 28 – 30 | 29 |
| Mo | 3.5 – 4.2 | 4 |
| Niadded for toughness | 2 – 2.5 | 2.2 |
| Mn | ≤ 0.3 | 0.2 |
| Si | ≤ 0.2 | 0.15 |
| P | ≤ 0.03 | — |
| S | ≤ 0.02 | — |
| Cu | ≤ 0.15 | — |
| Fe | balance | — |
S44800 As Welded — frequently asked
What is S44800 As Welded used for?
S44800 As Welded is typically used for seawater heat exchangers, chemical process equipment and high-chloride service piping. In short: purest super-ferritic grade; highest chloride resistance, ferritic; toughest 29Cr-4Mo variant.
What is the yield strength of S44800 As Welded?
S44800 As Welded has a typical yield strength of 470 MPa (68.2 ksi) and a tensile strength of 610 MPa (88.5 ksi) — stronger than 74% of stainless steel grades. Strength varies by condition: see the 3 listed tempers.
Is S44800 As Welded easy to machine?
Not especially — machinability is rated poor (33/100, worse than 57% of stainless steel grades). Machines like a tough ferritic stainless (~40% of 1212): rigid setups, sharp positive-rake carbide, heavy feeds and flood coolant to avoid work-hardened glazing and built-up edge.
Can S44800 As Welded be welded?
With care — weldability is rated fair (50/100). Weld autogenously by GTAW/PAW with very high-purity argon (trailing and backing gas), low heat input and scrupulous cleanliness; carbon, nitrogen or oxygen pickup embrittles the weld — avoid austenitic fillers where matching corrosion resistance is required, and never preheat above ~150 °C.
What surface finishes work on S44800 As Welded?
Pickle and passivate after hot work or welding to restore the Cr-Mo oxide film; electropolishing or mechanical polishing gives excellent seawater-service surfaces — no anodizing.
Can S44800 As Welded be formed, bent or molded?
Cold forms well for a super-ferritic in thin gauge (roll forming, tube making, moderate draws); use generous bend radii, expect higher springback than 304 and warm form ~150–250 °C for severe bends in heavier sections.
What is the maximum service temperature of S44800 As Welded?
S44800 As Welded 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.
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)
- AL 29-4-2 Alloy (UNS S44800) Technical Data Sheet — ATI / Allegheny Ludlum (2014)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels, and High-Performance Alloys (superferritic stainless steels) — ASM International (1990)
- Outokumpu Corrosion Handbook / Stainless Steel Handbook — Outokumpu (2020)
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.