Stainless Steel S44800 Annealed
Temper · default condition
UNS S44800
Standard stocked condition for all forming, welding and corrosion service; best ductility and toughness.
Values for the Annealed 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-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 |
AnnealedDefaultThis page 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 Annealed?
S44800 Annealed is S44800 in the Annealed temper — standard stocked condition for all forming, welding and corrosion service; best ductility and toughness. S44800 Annealed has a yield strength of 480 MPa (69.6 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 75% of stainless steel grades. Elongation at break is 25% and the elastic modulus is 200 GPa (29 Msi). S44800 Annealed 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).
Advantages
- Good corrosion resistance — 88/100, better than 97% of stainless steel grades
- High strength — 480 MPa (69.6 ksi), better than 75% of stainless steel grades
Limitations
- Limited service temperature — 300°C (572 °F), worse than 90% of stainless steel grades
S44800 Annealed properties
Typical room-temperature values for S44800 Annealed; 11 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 Annealed 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 Annealed has a yield strength of 480 MPa (69.6 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 75% of stainless steel grades. Elongation at break is 25% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
S44800 Annealed 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 Annealed conducts electricity at 2.3 % IACS, better than 55% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is excellent (88/100), better than 97% of stainless steel grades.
Sustainability4
Producing a kilogram of S44800 Annealed 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 Annealed's machinability is fair (35/100, better than 51% of stainless steel grades); weldability good (55/100); formability good (55/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with S44800 Annealed
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 Annealed — frequently asked
What is S44800 Annealed used for?
S44800 Annealed 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 Annealed?
S44800 Annealed has a typical yield strength of 480 MPa (69.6 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 75% of stainless steel grades. Strength varies by condition: see the 3 listed tempers.
Is S44800 Annealed easy to machine?
Not especially — machinability is rated fair (35/100, better than 51% 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 Annealed be welded?
Yes — weldability is rated good (55/100). 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 Annealed?
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 Annealed 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 Annealed?
S44800 Annealed 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.