Stainless Steel 1.4563-AT
Precip hard · default condition
EN 1.4563 · UNS N08031, N08028 · also Alloy 31 / Nicrofer 3127hMo
AT = solution annealed and quenched
Standard corrosion-service condition for plate, pipe, fittings and forgings — maximum corrosion resistance and ductility.
Values for the AT condition
Other 1.4563 tempers and conditions
1.4563 is listed in 3 conditions; see the grade overview at 1.4563.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
ATDefaultThis page Solution annealed and quenched | Standard corrosion-service condition for plate, pipe, fittings and forgings — maximum corrosion resistance and ductility. | 330 | 700 | 50 | 170 HB | — |
Cold drawn | Choose for close-tolerance bar, shafting and machined fittings where higher yield strength is wanted over maximum ductility. | 620 | 870 | 25 | 22 HRC | — |
Cold worked | Used where extra strength or springback is required in thin sections; corrosion resistance is essentially retained but ductility and formability drop sharply. | 700 | 950 | 18 | 30 HRC | — |
What is 1.4563-AT?
1.4563-AT is 1.4563 in the AT condition — standard corrosion-service condition for plate, pipe, fittings and forgings — maximum corrosion resistance and ductility. 1.4563-AT has a yield strength of 330 MPa (47.9 ksi) and a tensile strength of 700 MPa (102 ksi) — weaker than 57% of stainless steel grades. Elongation at break is 50% and the elastic modulus is 195 GPa (28.3 Msi). 1.4563-AT has a density of 8.02 g/cm³ (0.29 lb/in³), heavier than 97% of stainless steel grades. It melts at 1,320°C (2,408 °F).
Advantages
- Good corrosion resistance — 92/100, better than 99% of stainless steel grades
- Ductile — tolerates forming and impact — 50%, better than 90% of stainless steel grades
Limitations
- Poor heat conductor — 11 W/m·K (6.36 BTU/hr·ft·°F), worse than 99% of stainless steel grades
- High embodied carbon — 8 kg CO₂/kg, worse than 99% of stainless steel grades
- Difficult to machine — 22/100, worse than 95% of stainless steel grades
- Low electrical conductivity — 1.7 % IACS, worse than 93% of stainless steel grades
- Limited service temperature — 400°C (752 °F), worse than 78% of stainless steel grades
1.4563-AT properties
Typical room-temperature values for 1.4563-AT; 14 are specific to this condition. Other listed values are 1.4563 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
1.4563-AT has a density of 8.02 g/cm³ (0.29 lb/in³), heavier than 97% of stainless steel grades. It melts at 1,320°C (2,408 °F).
Mechanical14
1.4563-AT has a yield strength of 330 MPa (47.9 ksi) and a tensile strength of 700 MPa (102 ksi) — weaker than 57% of stainless steel grades. Elongation at break is 50% and the elastic modulus is 195 GPa (28.3 Msi).
Thermal5
1.4563-AT is rated for continuous service to 400°C (752 °F). It conducts heat at 11 W/m·K (6.36 BTU/hr·ft·°F), worse than 99% of stainless steel grades. Thermal expansion is 14.5 µm/m·K (8.06 µin/in·°F).
Electrical3
1.4563-AT conducts electricity at 1.7 % IACS, worse than 93% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is excellent (92/100), better than 99% of stainless steel grades.
Sustainability4
Producing a kilogram of 1.4563-AT takes about 100 MJ of energy and emits 8 kg of CO₂ — more than 98% of stainless steel grades. Typical recycled content is 40%.
Manufacturability7
1.4563-AT's machinability is poor (22/100, worse than 95% of stainless steel grades); weldability very good (75/100); formability good (65/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 1.4563-AT
Is 1.4563 easy to machine?
Very gummy and strongly work hardening — use rigid setups, positive-rake sharp carbide, low speed with heavy feed, never dwell, and flood high-pressure coolant.
Can 1.4563 be welded?
Weld with GTAW/GMAW/SMAW using overalloyed Ni-base filler (ERNiCrMo-3/-4 or matching 31 filler), low heat input, interpass <150 °C, no preheat, backing gas on root; PWHT normally not required.
Can 1.4563 be formed, bent or molded?
Cold forms well but needs ~50 % more force than 316L and generous springback allowance; hot work 1150–900 °C followed by solution anneal at ~1150–1180 °C and rapid quench.
What surface finishes work on 1.4563?
Pickle in HNO₃/HF or bead blast plus passivation to restore the passive film after welding; electropolishing gives the best surface for acid and pharma service.
1.4563 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 |
|---|---|---|
| Cextra low carbon | ≤ 0.02 | 0.01 |
| Si | ≤ 0.3 | 0.2 |
| Mn | ≤ 2 | 1 |
| P | ≤ 0.02 | 0.02 |
| S | ≤ 0.01 | 0 |
| Cr | 26 – 28 | 27 |
| Ni | 30 – 32 | 31 |
| Mo | 6 – 7 | 6.5 |
| Cuimproves hot sulfuric acid resistance | 1 – 1.4 | 1.2 |
| Nraises PREN and strength | 0.15 – 0.25 | 0.2 |
| Febalance, ~31–33 % | balance | — |
1.4563-AT — frequently asked
What is 1.4563-AT used for?
1.4563-AT is typically used for sulfuric acid coolers and heat exchangers, phosphoric acid production, flue gas desulfurization and chemical process equipment. In short: upgrade from 904L; hot acid corrosion resistance; hardest of the family to machine.
What is the yield strength of 1.4563-AT?
1.4563-AT has a typical yield strength of 330 MPa (47.9 ksi) and a tensile strength of 700 MPa (102 ksi) — weaker than 57% of stainless steel grades. Strength varies by condition: see the 3 listed tempers.
Is 1.4563-AT easy to machine?
Not especially — machinability is rated poor (22/100, worse than 95% of stainless steel grades). Very gummy and strongly work hardening — use rigid setups, positive-rake sharp carbide, low speed with heavy feed, never dwell, and flood high-pressure coolant.
Can 1.4563-AT be welded?
Yes — weldability is rated very good (75/100). Weld with GTAW/GMAW/SMAW using overalloyed Ni-base filler (ERNiCrMo-3/-4 or matching 31 filler), low heat input, interpass <150 °C, no preheat, backing gas on root; PWHT normally not required.
What surface finishes work on 1.4563-AT?
Pickle in HNO₃/HF or bead blast plus passivation to restore the passive film after welding; electropolishing gives the best surface for acid and pharma service.
Can 1.4563-AT be formed, bent or molded?
Cold forms well but needs ~50 % more force than 316L and generous springback allowance; hot work 1150–900 °C followed by solution anneal at ~1150–1180 °C and rapid quench.
What is the maximum service temperature of 1.4563-AT?
1.4563-AT 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 1.4563-AT and 1.4563-CW?
AT is the default condition — standard corrosion-service condition for plate, pipe, fittings and forgings — maximum corrosion resistance and ductility. CW: used where extra strength or springback is required in thin sections; corrosion resistance is essentially retained but ductility and formability drop sharply. Yield strength is 330 MPa in AT versus 700 MPa in CW.
Sources
- EN 10088-1/-2 Stainless steels — grades and technical delivery conditions (X1NiCrMoCu31-27-4, 1.4563) — CEN (2014)
- ASTM B625 / B649 / B622 (UNS N08031 plate, sheet, strip, bar and tube) — ASTM International (2023)
- VDM Alloy 31 / Nicrofer 3127 hMo material data sheet — VDM Metals (2020)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- Corrosion data for high-alloy austenitic stainless steels (CPT/CCT, sulfuric & phosphoric acid isocorrosion) — Outokumpu / Sandvik technical literature (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.