Stainless Steel 1.4439-SA (Solution annealed)
Heat-treated state · default condition
EN 1.4439
Standard supply condition for plate, bar, tube and fittings — maximum corrosion resistance and ductility.
Values for the SA condition
Other 1.4439 tempers and conditions
1.4439 is listed in 5 conditions; see the grade overview at 1.4439.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
SADefaultThis page Solution annealed | Standard supply condition for plate, bar, tube and fittings — maximum corrosion resistance and ductility. | 320 | 640 | 45 | 190 HB | — |
As-welded deposit | For weldment design checks; use over-alloyed filler (ER317LMN, 625 or 2209) and expect slightly lower ductility. | 380 | 620 | 30 | 200 HB | 2 % IACS |
Cold drawn | Bar and shafting where higher strength and tighter tolerance than annealed are needed. | 480 | 720 | 30 | 20 HRC | 2 % IACS |
1/4 Hard | Springy strip or lightly stiffened panels where moderate strength gain is wanted. | 560 | 820 | 20 | 25 HRC | 2 % IACS |
1/2 Hard | Rarely stocked; used for high-strength clamps, springs and wire in aggressive chloride media. | 780 | 970 | 12 | 31 HRC | 2 % IACS |
What is 1.4439-SA?
1.4439-SA is 1.4439 heat treated to SA — standard supply condition for plate, bar, tube and fittings — maximum corrosion resistance and ductility. 1.4439-SA has a yield strength of 320 MPa (46.4 ksi) and a tensile strength of 640 MPa (92.8 ksi) — weaker than 60% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 200 GPa (29 Msi). 1.4439-SA 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
- Tough — resists crack growth — 220 MPa·√m (200.2 ksi·√in), better than 97% of stainless steel grades
- Good corrosion resistance — 80/100, better than 88% of stainless steel grades
- Readily welded — 80/100, better than 80% of stainless steel grades
- Ductile — tolerates forming and impact — 45%, better than 76% of stainless steel grades
- Forms and bends easily — 68/100, better than 75% of stainless steel grades
Limitations
- Low electrical conductivity — 2 % IACS, worse than 77% of stainless steel grades
- High embodied carbon — 5.5 kg CO₂/kg, worse than 77% of stainless steel grades
1.4439-SA properties
Typical room-temperature values for 1.4439-SA; 11 are specific to this condition. Other listed values are 1.4439 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
1.4439-SA 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
1.4439-SA has a yield strength of 320 MPa (46.4 ksi) and a tensile strength of 640 MPa (92.8 ksi) — weaker than 60% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
1.4439-SA is rated for continuous service to 450°C (842 °F). It conducts heat at 14 W/m·K (8.09 BTU/hr·ft·°F), worse than 80% of stainless steel grades. Thermal expansion is 16.5 µm/m·K (9.17 µin/in·°F).
Electrical3
1.4439-SA conducts electricity at 2 % IACS, worse than 77% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is very good (80/100), better than 88% of stainless steel grades.
Sustainability4
Producing a kilogram of 1.4439-SA takes about 62 MJ of energy and emits 5.5 kg of CO₂ — more than 75% of stainless steel grades. Typical recycled content is 45%.
Manufacturability7
1.4439-SA's machinability is poor (32/100, worse than 62% of stainless steel grades); weldability very good (80/100); formability good (68/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 1.4439-SA
Is 1.4439 easy to machine?
Tough and gummy with high work hardening — use rigid setups, positive-rake coated carbide, 25–60 m/min, heavy feed and flood coolant; never dwell or let the tool rub.
Can 1.4439 be welded?
Readily welded by GTAW/GMAW/SMAW with no preheat or PWHT; use over-alloyed filler (ER/E317LMN, ERNiCrMo-3 or 2209), low heat input and back-purge to keep weld-metal PREN and avoid hot cracking.
Can 1.4439 be formed, bent or molded?
Cold forms and deep draws well but needs ~50 % more press force and springback allowance than 304; hot work 1150–900 °C followed by full solution anneal and water quench.
What surface finishes work on 1.4439?
Pickle (HNO₃/HF) and passivate after welding or grinding to restore the passive film; electropolishing or mechanical polishing to Ra <0.5 µm for pharma/chemical service — no anodizing.
1.4439 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-carbon, avoids sensitization | ≤ 0.03 | 0.02 |
| Si | ≤ 1 | 0.5 |
| Mn | ≤ 2 | 1.5 |
| P | ≤ 0.05 | — |
| SASTM A240 S31726 allows 0.030 max | ≤ 0.02 | — |
| CrS31726: 17.0–20.0 | 16.5 – 18.5 | 17.5 |
| NiS31726: 13.5–17.5 | 12.5 – 14.5 | 13.5 |
| Mopitting resistance | 4 – 5 | 4.5 |
| Nsolid-solution strengthening; S31726: 0.10–0.20 | 0.12 – 0.22 | 0.17 |
| Fe | balance | — |
1.4439-SA — frequently asked
What is 1.4439-SA used for?
1.4439-SA is typically used for seawater desalination, chemical tanks, offshore equipment and pulp & paper. In short: high-PREN austenitic; stronger than 316L; chloride pitting resistant.
What is the yield strength of 1.4439-SA?
1.4439-SA has a typical yield strength of 320 MPa (46.4 ksi) and a tensile strength of 640 MPa (92.8 ksi) — weaker than 60% of stainless steel grades. Strength varies by condition: see the 5 listed tempers.
Is 1.4439-SA easy to machine?
Not especially — machinability is rated poor (32/100, worse than 62% of stainless steel grades). Tough and gummy with high work hardening — use rigid setups, positive-rake coated carbide, 25–60 m/min, heavy feed and flood coolant; never dwell or let the tool rub.
Can 1.4439-SA be welded?
Yes — weldability is rated very good (80/100). Readily welded by GTAW/GMAW/SMAW with no preheat or PWHT; use over-alloyed filler (ER/E317LMN, ERNiCrMo-3 or 2209), low heat input and back-purge to keep weld-metal PREN and avoid hot cracking.
What surface finishes work on 1.4439-SA?
Pickle (HNO₃/HF) and passivate after welding or grinding to restore the passive film; electropolishing or mechanical polishing to Ra <0.5 µm for pharma/chemical service — no anodizing.
Can 1.4439-SA be formed, bent or molded?
Cold forms and deep draws well but needs ~50 % more press force and springback allowance than 304; hot work 1150–900 °C followed by full solution anneal and water quench.
What is the maximum service temperature of 1.4439-SA?
1.4439-SA is rated for continuous use to about 450°C (842 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 1.4439-SA and 1.4439-CD?
SA is the default condition — standard supply condition for plate, bar, tube and fittings — maximum corrosion resistance and ductility. CD: bar and shafting where higher strength and tighter tolerance than annealed are needed. Yield strength is 320 MPa in SA versus 480 MPa in CD.
Sources
- EN 10088-1/-2/-3 Stainless steels — X2CrNiMoN17-13-5 (1.4439) — CEN (2014)
- ASTM A240/A240M — Cr and Cr-Ni stainless plate, sheet and strip (UNS S31726) — ASTM (2022)
- ASTM A312 / A213 — welded and seamless austenitic stainless pipe and tube — ASTM (2022)
- Outokumpu 4439 / 317LMN datasheet — Outokumpu (2023)
- ASM Handbook Vol.1 — Properties of Stainless Steels — ASM International (1990)
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.