Stainless Steel 1.4588-SA
Heat-treated state · default condition
EN 1.4588
SA = solution annealed ~1120–1180 °C + rapid water quench
Standard and essentially only supply condition; required to dissolve interdendritic sigma/chi and secure full corrosion performance.
Values for the SA condition
Other 1.4588 tempers and conditions
1.4588 is listed in 4 conditions; see the grade overview at 1.4588.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
SA | Heavy-section castings where slower quench rate and coarser dendrites give slightly lower ductility/toughness at the same specified minima. | 290 | 565 | 38 | 165 HB | 2 % IACS |
SADefaultThis page Solution annealed ~1120–1180 °C + rapid water quench | Standard and essentially only supply condition; required to dissolve interdendritic sigma/chi and secure full corrosion performance. | 300 | 585 | 45 | 170 HB | 2 % IACS |
Spheroidize annealed | Only for rough/non-corrosion-critical hardware; interdendritic sigma and Mo segregation sharply reduce pitting resistance and toughness. | 300 | 540 | 20 | 14 HRC | 2 % IACS |
Hot isostatically pressed then solution annealed and quenched | Choose for pressure-retaining or radiographically critical pump/valve castings where microporosity must be closed and ductility/toughness maximised. | 310 | 610 | 50 | 170 HB | 2 % IACS |
What is 1.4588-SA?
1.4588-SA is 1.4588 heat treated to SA — standard and essentially only supply condition; required to dissolve interdendritic sigma/chi and secure full corrosion performance. 1.4588-SA has a yield strength of 300 MPa (43.5 ksi) and a tensile strength of 585 MPa (84.8 ksi) — weaker than 68% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 195 GPa (28.3 Msi). 1.4588-SA has a density of 8 g/cm³ (0.289 lb/in³), heavier than 92% of stainless steel grades. It melts at 1,320°C (2,408 °F).
Advantages
- Good corrosion resistance — 84/100, better than 91% of stainless steel grades
- Ductile — tolerates forming and impact — 45%, better than 76% of stainless steel grades
Limitations
- Poor heat conductor — 12 W/m·K (6.93 BTU/hr·ft·°F), worse than 93% of stainless steel grades
- High embodied carbon — 6.5 kg CO₂/kg, worse than 93% of stainless steel grades
- Difficult to machine — 25/100, worse than 88% of stainless steel grades
- Limited service temperature — 400°C (752 °F), worse than 78% of stainless steel grades
- Low electrical conductivity — 2 % IACS, worse than 77% of stainless steel grades
1.4588-SA properties
Typical room-temperature values for 1.4588-SA; 23 are specific to this condition. Other listed values are 1.4588 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
1.4588-SA has a density of 8 g/cm³ (0.289 lb/in³), heavier than 92% of stainless steel grades. It melts at 1,320°C (2,408 °F).
Mechanical16
1.4588-SA has a yield strength of 300 MPa (43.5 ksi) and a tensile strength of 585 MPa (84.8 ksi) — weaker than 68% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 195 GPa (28.3 Msi).
Thermal6
1.4588-SA is rated for continuous service to 400°C (752 °F). It conducts heat at 12 W/m·K (6.93 BTU/hr·ft·°F), worse than 93% of stainless steel grades. Thermal expansion is 14.6 µm/m·K (8.11 µin/in·°F).
Electrical3
1.4588-SA conducts electricity at 2 % IACS, worse than 77% 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 1.4588-SA takes about 85 MJ of energy and emits 6.5 kg of CO₂ — more than 92% of stainless steel grades. Typical recycled content is 40%.
Manufacturability8
1.4588-SA's machinability is poor (25/100, worse than 88% of stainless steel grades); weldability good (60/100); formability poor (30/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 1.4588-SA
Is 1.4588 easy to machine?
Machine like AL-6XN/904L: rigid setups, sharp positive-rake carbide, heavy flood coolant, low speed with high feed to avoid work hardening and glazing; expect ~30 % of 1212 rates.
Can 1.4588 be welded?
GTAW/GMAW with overalloyed Ni-base filler (ERNiCrMo-3/-4) to compensate Mo dilution; low heat input, no preheat, interpass < 150 °C, and no post-weld stress relief in the 500–900 °C range.
Can 1.4588 be formed, bent or molded?
Supplied as sand/investment/centrifugal castings — design generous fillets and directional feeding for the wide freezing range; always re-solution anneal and water quench after casting, HIP or major repair welding.
What surface finishes work on 1.4588?
Pickle in HNO₃-HF then passivate to restore the Cr-Mo-N film; grind out weld heat tint fully, and avoid carbon-steel contact tooling to prevent iron contamination and later pitting.
1.4588 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 to avoid carbide/sigma precipitation | ≤ 0.03 | 0.02 |
| Si | ≤ 1 | 0.6 |
| MnA351 CK3MCuN limits Mn to 1.20 max | ≤ 2 | 1 |
| P | ≤ 0.05 | — |
| S | ≤ 0.01 | — |
| Cr | 19 – 21 | 20 |
| NiEN 1.4588 is high-Ni; A351 CK3MCuN is 17.5–19.5 Ni | 24 – 26 | 25 |
| Mo | 6 – 7 | 6.5 |
| CuA351 CK3MCuN: 0.50–1.00 Cu | 1 – 2 | 1.5 |
| N | 0.15 – 0.25 | 0.2 |
| Fe | balance | — |
1.4588-SA — frequently asked
What is 1.4588-SA used for?
1.4588-SA is typically used for desalination pump castings, chemical process valve bodies, seawater pump impellers and casings, flue gas desulfurization scrubber parts, offshore firewater pump components and pulp bleach plant fittings. In short: strongest cast superaustenitic here; 6Mo chloride resistance; desalination pump grade.
What is the yield strength of 1.4588-SA?
1.4588-SA has a typical yield strength of 300 MPa (43.5 ksi) and a tensile strength of 585 MPa (84.8 ksi) — weaker than 68% of stainless steel grades. Strength varies by condition: see the 4 listed tempers.
Is 1.4588-SA easy to machine?
Not especially — machinability is rated poor (25/100, worse than 88% of stainless steel grades). Machine like AL-6XN/904L: rigid setups, sharp positive-rake carbide, heavy flood coolant, low speed with high feed to avoid work hardening and glazing; expect ~30 % of 1212 rates.
Can 1.4588-SA be welded?
Yes — weldability is rated good (60/100). GTAW/GMAW with overalloyed Ni-base filler (ERNiCrMo-3/-4) to compensate Mo dilution; low heat input, no preheat, interpass < 150 °C, and no post-weld stress relief in the 500–900 °C range.
What surface finishes work on 1.4588-SA?
Pickle in HNO₃-HF then passivate to restore the Cr-Mo-N film; grind out weld heat tint fully, and avoid carbon-steel contact tooling to prevent iron contamination and later pitting.
Can 1.4588-SA be formed, bent or molded?
Supplied as sand/investment/centrifugal castings — design generous fillets and directional feeding for the wide freezing range; always re-solution anneal and water quench after casting, HIP or major repair welding.
What is the maximum service temperature of 1.4588-SA?
1.4588-SA is rated for continuous use to about 400°C (752 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 1.4588-SA and 1.4588 SA-HW?
SA is the default condition — standard and essentially only supply condition; required to dissolve interdendritic sigma/chi and secure full corrosion performance. SA-HW: heavy-section castings where slower quench rate and coarser dendrites give slightly lower ductility/toughness at the same specified minima. Yield strength is 300 MPa in SA versus 290 MPa in SA-HW.
Sources
- EN 10283 — Corrosion resistant steel castings — CEN (2010)
- ASTM A351/A351M — Castings, Austenitic, for Pressure-Containing Parts (CK3MCuN, J93254) — ASTM (2023)
- ASTM A743/A744 — Corrosion-resistant iron-chromium-nickel castings — ASTM (2021)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- 6 % Mo superaustenitic stainless steel data (254 SMO / AL-6XN class) — Outokumpu / ATI (2022)
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.