Stainless Steel 1.4449-AT (Solution annealed)
Precip hard · default condition
EN 1.4449
Standard stocked condition for plate, sheet, tube and forgings; best corrosion resistance and formability.
Values for the AT condition
Other 1.4449 tempers and conditions
1.4449 is listed in 7 conditions; see the grade overview at 1.4449.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Hot rolled | Heavy plate and hot-finished bar/section for structural and pressure parts where surface finish is secondary. | 250 | 540 | 45 | 155 HB | 2.3 % IACS |
ATDefaultThis page Solution annealed | Standard stocked condition for plate, sheet, tube and forgings; best corrosion resistance and formability. | 260 | 560 | 45 | 160 HB | — |
Cold drawn | Bright bar for shafts and machined fittings; higher strength and better surface than hot-finished bar. | 450 | 690 | 25 | 18 HRC | 2.3 % IACS |
1/4 Hard | Light cold work for stiffer sheet-metal parts still needing moderate bending. | 500 | 750 | 25 | 21 HRC | 2.3 % IACS |
1/2 Hard | Choose for springy clips and load-bearing thin sheet with only gentle forming. | 650 | 900 | 12 | 28 HRC | 2.3 % IACS |
3/4 Hard | High-strength strip for flat springs and shims where forming is minimal. | 800 | 1,030 | 8 | 32 HRC | 2.3 % IACS |
Full Hard | Maximum strength condition for spring wire, straps and cut blanks; essentially no formability. | 1,000 | 1,200 | 5 | 38 HRC | 2.3 % IACS |
What is 1.4449-AT?
1.4449-AT is 1.4449 in the AT condition — standard stocked condition for plate, sheet, tube and forgings; best corrosion resistance and formability. 1.4449-AT has a yield strength of 260 MPa (37.7 ksi) and a tensile strength of 560 MPa (81.2 ksi) — weaker than 84% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 200 GPa (29 Msi). 1.4449-AT has a density of 8 g/cm³ (0.289 lb/in³), heavier than 92% of stainless steel grades. It melts at 1,370°C (2,498 °F).
Advantages
- Forms and bends easily — 85/100, better than 95% of stainless steel grades
- Polishes to a fine finish — 80/100, better than 89% of stainless steel grades
- Readily welded — 85/100, better than 87% of stainless steel grades
- Good corrosion resistance — 78/100, better than 84% of stainless steel grades
- Ductile — tolerates forming and impact — 45%, better than 76% of stainless steel grades
Limitations
- Low strength — 260 MPa (37.7 ksi), worse than 84% of stainless steel grades
1.4449-AT properties
Typical room-temperature values for 1.4449-AT; 12 are specific to this condition. Other listed values are 1.4449 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
1.4449-AT has a density of 8 g/cm³ (0.289 lb/in³), heavier than 92% of stainless steel grades. It melts at 1,370°C (2,498 °F).
Mechanical16
1.4449-AT has a yield strength of 260 MPa (37.7 ksi) and a tensile strength of 560 MPa (81.2 ksi) — weaker than 84% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
1.4449-AT is rated for continuous service to 800°C (1,472 °F). It conducts heat at 15 W/m·K (8.67 BTU/hr·ft·°F), worse than 59% of stainless steel grades. Thermal expansion is 16 µm/m·K (8.89 µin/in·°F).
Electrical3
1.4449-AT conducts electricity at 2.3 % IACS, better than 55% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is very good (78/100), better than 84% of stainless steel grades.
Sustainability4
Producing a kilogram of 1.4449-AT takes about 53 MJ of energy and emits 4.6 kg of CO₂ — less than 67% of stainless steel grades. Typical recycled content is 60%.
Manufacturability8
1.4449-AT's machinability is fair (40/100, better than 72% of stainless steel grades); weldability excellent (85/100); formability excellent (85/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 1.4449-AT
Is 1.4449 easy to machine?
Gummy, work-hardening austenitic: use rigid setups, sharp positive-rake carbide, 60–120 m/min, heavy positive feed to avoid dwell, and flood coolant to prevent built-up edge.
Can 1.4449 be welded?
Readily welded by TIG/MIG/SMAW/laser with 316L or 318 (E/ER 316L, 19 12 3 L) filler, no preheat, low interpass temperature; standard carbon means avoid prolonged 500–800 °C exposure to prevent sensitization of thick sections.
Can 1.4449 be formed, bent or molded?
Excellent cold formability for deep drawing and bending but high work hardening and springback — allow 30–50 % more press force than carbon steel and interstage anneal at 1050–1100 °C for severe draws.
What surface finishes work on 1.4449?
Not anodizable; finish by pickling and passivation after welding, electropolishing for hygienic surfaces, or mechanical grinding/bright polishing (2B, No.4, mirror No.8).
1.4449 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 |
|---|---|---|
| Cstandard-carbon Mo grade | ≤ 0.04 | 0.03 |
| Si | ≤ 1 | 0.5 |
| Mn | ≤ 2 | 1.5 |
| P | ≤ 0.05 | 0.03 |
| S | ≤ 0.02 | 0.01 |
| Cr | 17 – 19 | 18 |
| Ni | 11 – 14 | 12 |
| Mo | 2.5 – 3 | 2.7 |
| N | ≤ 0.11 | 0.05 |
| Fe | balance | — |
1.4449-AT — frequently asked
What is 1.4449-AT used for?
1.4449-AT is typically used for pressure vessels, structural fittings, chemical equipment and marine hardware. In short: structural 316 grade; cold-worked tempers to full hard; higher temperature tolerance.
What is the yield strength of 1.4449-AT?
1.4449-AT has a typical yield strength of 260 MPa (37.7 ksi) and a tensile strength of 560 MPa (81.2 ksi) — weaker than 84% of stainless steel grades. Strength varies by condition: see the 7 listed tempers.
Is 1.4449-AT easy to machine?
Not especially — machinability is rated fair (40/100, better than 72% of stainless steel grades). Gummy, work-hardening austenitic: use rigid setups, sharp positive-rake carbide, 60–120 m/min, heavy positive feed to avoid dwell, and flood coolant to prevent built-up edge.
Can 1.4449-AT be welded?
Yes — weldability is rated excellent (85/100). Readily welded by TIG/MIG/SMAW/laser with 316L or 318 (E/ER 316L, 19 12 3 L) filler, no preheat, low interpass temperature; standard carbon means avoid prolonged 500–800 °C exposure to prevent sensitization of thick sections.
What surface finishes work on 1.4449-AT?
Not anodizable; finish by pickling and passivation after welding, electropolishing for hygienic surfaces, or mechanical grinding/bright polishing (2B, No.4, mirror No.8).
Can 1.4449-AT be formed, bent or molded?
Excellent cold formability for deep drawing and bending but high work hardening and springback — allow 30–50 % more press force than carbon steel and interstage anneal at 1050–1100 °C for severe draws.
What is the maximum service temperature of 1.4449-AT?
1.4449-AT is rated for continuous use to about 800°C (1,472 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 1.4449-AT and 1.4449 CWFH?
AT is the default condition — standard stocked condition for plate, sheet, tube and forgings; best corrosion resistance and formability. CWFH: maximum strength condition for spring wire, straps and cut blanks; essentially no formability. Yield strength is 260 MPa in AT versus 1,000 MPa in CWFH.
Sources
- EN 10088-1 Stainless steels — List of stainless steels — CEN (2014)
- EN 10088-2 Technical delivery conditions for sheet/plate and strip — CEN (2014)
- ASTM A240/A276 (S31600/316 comparable grade) — ASTM (2023)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels — ASM International (1990)
- Outokumpu Stainless Steel Handbook / grade datasheets 4401-4436 — 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.