Stainless Steel 1.4587-AC (Spheroidize annealed)
Heat-treated state
EN 1.4587
Only for rough stock or non-corrosive structural use; interdendritic Mo segregation and sigma/chi phase sharply reduce toughness and pitting resistance.
Values for the AC condition
Other 1.4587 tempers and conditions
1.4587 is listed in 3 conditions; see the grade overview at 1.4587.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
ATDefault solution annealed 1120–1180 °C and water quenched (as-supplied casting) | Standard delivery condition for all pressure and corrosion-service castings; maximum corrosion resistance and toughness. | 260 | 520 | 40 | 165 HB | 1.7 % IACS |
hot isostatically pressed then solution annealed and quenched | Choose for thick-section or high-integrity pump/valve castings where micro-shrinkage porosity must be closed for full ductility and NDT acceptance. | 270 | 545 | 45 | 170 HB | 1.7 % IACS |
ACThis page Spheroidize annealed | Only for rough stock or non-corrosive structural use; interdendritic Mo segregation and sigma/chi phase sharply reduce toughness and pitting resistance. | 280 | 500 | 20 | 185 HB | 1.7 % IACS |
What is 1.4587-AC?
1.4587-AC is 1.4587 heat treated to AC — only for rough stock or non-corrosive structural use; interdendritic Mo segregation and sigma/chi phase sharply reduce toughness and pitting resistance. 1.4587-AC has a yield strength of 280 MPa (40.6 ksi) and a tensile strength of 500 MPa (72.5 ksi) — weaker than 75% of stainless steel grades. Elongation at break is 20% and the elastic modulus is 195 GPa (28.3 Msi). 1.4587-AC has a density of 8 g/cm³ (0.289 lb/in³), heavier than 92% of stainless steel grades. It melts at 1,330°C (2,426 °F). AT is the default condition FabDigit quotes; AC is available on request or by drawing note.
Limitations
- Difficult to machine — 20/100, worse than 98% of stainless steel grades
- Poor heat conductor — 12 W/m·K (6.93 BTU/hr·ft·°F), worse than 93% of stainless steel grades
- Low electrical conductivity — 1.7 % IACS, worse than 93% of stainless steel grades
- Limited formability — 15/100, worse than 91% of stainless steel grades
- Limited service temperature — 300°C (572 °F), worse than 90% of stainless steel grades
1.4587-AC properties
Typical room-temperature values for 1.4587-AC; 23 are specific to this condition. Other listed values are 1.4587 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
1.4587-AC has a density of 8 g/cm³ (0.289 lb/in³), heavier than 92% of stainless steel grades. It melts at 1,330°C (2,426 °F).
Mechanical15
1.4587-AC has a yield strength of 280 MPa (40.6 ksi) and a tensile strength of 500 MPa (72.5 ksi) — weaker than 75% of stainless steel grades. Elongation at break is 20% and the elastic modulus is 195 GPa (28.3 Msi).
Thermal6
1.4587-AC is rated for continuous service to 300°C (572 °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 15.5 µm/m·K (8.61 µin/in·°F).
Electrical3
1.4587-AC conducts electricity at 1.7 % IACS, worse than 93% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (68/100), better than 63% of stainless steel grades.
Sustainability4
Producing a kilogram of 1.4587-AC takes about 72 MJ of energy and emits 5.5 kg of CO₂ — more than 83% of stainless steel grades. Typical recycled content is 55%.
Manufacturability7
1.4587-AC's machinability is poor (20/100, worse than 98% of stainless steel grades); weldability fair (45/100); formability poor (15/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 1.4587-AC
Is 1.4587 easy to machine?
Rigid setup, sharp positive-rake carbide, low speed / heavy positive feed and flood coolant — the alloy work-hardens badly and must never be allowed to rub.
Can 1.4587 be welded?
GTAW/SMAW with over-alloyed Ni-base filler (ERNiCrMo-3 625 or ERNiCrMo-13 59), low heat input, interpass < 150 °C; solution re-anneal after major repairs if service is severe.
Can 1.4587 be formed, bent or molded?
Casting grade — pour hot with generous risering to counter the wide freezing range; hot straightening at 1050–1150 °C only, followed by re-solution treatment.
What surface finishes work on 1.4587?
Pickle and passivate in HNO₃-HF after heat treatment to remove scale and restore the passive film; grind/polish for hygienic or high-velocity flow surfaces.
1.4587 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 cast grade | ≤ 0.03 | 0.02 |
| Si | ≤ 1 | 0.6 |
| Mn | ≤ 2 | 1 |
| P | ≤ 0.04 | — |
| S | ≤ 0.02 | — |
| Cr | 24 – 26 | 25 |
| NiSCC resistance | 28 – 30 | 29 |
| Mo | 4.5 – 5.5 | 5 |
| Cuimproves reducing-acid resistance | 1.5 – 2.5 | 2 |
| Nraises PREN and yield strength | 0.1 – 0.25 | 0.18 |
| Fe | balance | — |
1.4587-AC — frequently asked
What is 1.4587-AC used for?
1.4587-AC is typically used for sulfuric acid plant castings, seawater process pump casings, chemical process valve bodies, acid transfer pump impellers, flue gas desulfurization components and pickling and acid regeneration equipment. In short: highest corrosion rating here; nitrogen-plus-copper superaustenitic; severe acid service castings.
What is the yield strength of 1.4587-AC?
1.4587-AC has a typical yield strength of 280 MPa (40.6 ksi) and a tensile strength of 500 MPa (72.5 ksi) — weaker than 75% of stainless steel grades. Strength varies by condition: see the 3 listed tempers.
Is 1.4587-AC easy to machine?
Not especially — machinability is rated poor (20/100, worse than 98% of stainless steel grades). Rigid setup, sharp positive-rake carbide, low speed / heavy positive feed and flood coolant — the alloy work-hardens badly and must never be allowed to rub.
Can 1.4587-AC be welded?
With care — weldability is rated fair (45/100). GTAW/SMAW with over-alloyed Ni-base filler (ERNiCrMo-3 625 or ERNiCrMo-13 59), low heat input, interpass < 150 °C; solution re-anneal after major repairs if service is severe.
What surface finishes work on 1.4587-AC?
Pickle and passivate in HNO₃-HF after heat treatment to remove scale and restore the passive film; grind/polish for hygienic or high-velocity flow surfaces.
Can 1.4587-AC be formed, bent or molded?
Casting grade — pour hot with generous risering to counter the wide freezing range; hot straightening at 1050–1150 °C only, followed by re-solution treatment.
What is the maximum service temperature of 1.4587-AC?
1.4587-AC 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.
What is the difference between 1.4587-AT and 1.4587-AC?
AT is the default condition — standard delivery condition for all pressure and corrosion-service castings; maximum corrosion resistance and toughness. AC: only for rough stock or non-corrosive structural use; interdendritic Mo segregation and sigma/chi phase sharply reduce toughness and pitting resistance. Yield strength is 260 MPa in AT versus 280 MPa in AC.
Sources
- EN 10213 — Steel castings for pressure purposes — CEN (2016)
- EN 10283 — Corrosion resistant steel castings — CEN (2010)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- Superaustenitic stainless (alloy 28 / 904L class) corrosion and physical data — Sandvik / Outokumpu (2021)
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.