Stainless Steel 1.4971-SA (Solution annealed)
Heat-treated state · default condition
EN 1.4971
Standard stocked condition for sheet, bar and forgings: maximum ductility and creep-rupture performance for long-term high-temperature service.
Values for the SA condition
Other 1.4971 tempers and conditions
1.4971 is listed in 5 conditions; see the grade overview at 1.4971.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
SADefaultThis page Solution annealed | Standard stocked condition for sheet, bar and forgings: maximum ductility and creep-rupture performance for long-term high-temperature service. | 400 | 815 | 45 | 190 HB | — |
Hot rolled | Mill condition for heavy bar and forgings before final solution treatment; use only where a subsequent heat treatment is planned. | 470 | 860 | 35 | 17 HRC | 1.9 % IACS |
Solution annealed and aged | Pick when higher room- and mid-temperature strength/hardness is needed (turbine bolting, discs); carbide/nitride precipitation costs ductility and impact toughness. | 620 | 1,000 | 25 | 27 HRC | — |
Cold drawn | Cold-finished bar and fastener wire: raised yield strength and better surface/tolerance, but residual cold work limits long-term use above ~600 °C. | 750 | 1,000 | 20 | 26 HRC | 1.9 % IACS |
Cold worked and stress-relieved/aged | Highest-strength commercial condition, used for hot-service studs and bolts where relaxation resistance to ~700 °C matters. | 900 | 1,150 | 15 | 32 HRC | 1.9 % IACS |
What is 1.4971-SA?
1.4971-SA is 1.4971 heat treated to SA — standard stocked condition for sheet, bar and forgings: maximum ductility and creep-rupture performance for long-term high-temperature service. 1.4971-SA has a yield strength of 400 MPa (58 ksi) and a tensile strength of 815 MPa (118 ksi) — stronger than 57% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 200 GPa (29 Msi). 1.4971-SA has a density of 8.19 g/cm³ (0.296 lb/in³), heavier than 100% of stainless steel grades. It melts at 1,300°C (2,372 °F).
Advantages
- High service temperature — 900°C (1,652 °F), better than 85% of stainless steel grades
- Ductile — tolerates forming and impact — 45%, better than 76% of stainless steel grades
Limitations
- High embodied carbon — 9.5 kg CO₂/kg, worse than 100% of stainless steel grades
- Poor heat conductor — 12.4 W/m·K (7.16 BTU/hr·ft·°F), worse than 91% of stainless steel grades
- Difficult to machine — 25/100, worse than 88% of stainless steel grades
- Low electrical conductivity — 1.9 % IACS, worse than 84% of stainless steel grades
- Hard to polish — 60/100, worse than 80% of stainless steel grades
1.4971-SA properties
Typical room-temperature values for 1.4971-SA; 12 are specific to this condition. Other listed values are 1.4971 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
1.4971-SA has a density of 8.19 g/cm³ (0.296 lb/in³), heavier than 100% of stainless steel grades. It melts at 1,300°C (2,372 °F).
Mechanical13
1.4971-SA has a yield strength of 400 MPa (58 ksi) and a tensile strength of 815 MPa (118 ksi) — stronger than 57% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 200 GPa (29 Msi).
Thermal5
1.4971-SA is rated for continuous service to 900°C (1,652 °F). It conducts heat at 12.4 W/m·K (7.16 BTU/hr·ft·°F), worse than 91% of stainless steel grades. Thermal expansion is 15.7 µm/m·K (8.72 µin/in·°F).
Electrical3
1.4971-SA conducts electricity at 1.9 % IACS, worse than 84% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (66/100), better than 59% of stainless steel grades.
Sustainability4
Producing a kilogram of 1.4971-SA takes about 110 MJ of energy and emits 9.5 kg of CO₂ — more than 99% of stainless steel grades. Typical recycled content is 40%.
Manufacturability7
1.4971-SA's machinability is poor (25/100, worse than 88% of stainless steel grades); weldability good (60/100); formability good (55/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 1.4971-SA
Is 1.4971 easy to machine?
Treat as a superalloy: rigid setups, sharp positive-rake carbide or ceramic tooling, low surface speed with heavy feed, flood coolant, and avoid dwelling — the alloy work-hardens rapidly and galls.
Can 1.4971 be welded?
GTAW/GMAW with matching N-155 (or Haynes 556/inconel-type) filler; clean joints, low heat input, no preheat needed, and re-solution treat heavily welded assemblies to restore creep properties.
Can 1.4971 be formed, bent or molded?
Hot work at 1050–1180 °C and finish above ~950 °C; cold forming needs 2–3× the force of 304 with frequent 1175 °C intermediate anneals.
What surface finishes work on 1.4971?
Pickle/passivate or bead blast after hot working; not anodizable — use aluminide, MCrAlY or ceramic thermal-barrier coatings for the hottest oxidation/sulfidation duty.
1.4971 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 |
|---|---|---|
| C | 0.08 – 0.16 | 0.12 |
| Si | ≤ 0.75 | 0.4 |
| Mn | 1 – 2 | 1.5 |
| P | ≤ 0.04 | — |
| S | ≤ 0.03 | — |
| Cr | 20 – 22.5 | 21 |
| Ni | 19 – 21 | 20 |
| Co | 18.5 – 21 | 20 |
| Mo | 2.5 – 3.5 | 3 |
| W | 2 – 3 | 2.5 |
| NbNb (+Ta) | 0.75 – 1.25 | 1 |
| Nsolid-solution/nitride strengthening | 0.1 – 0.2 | 0.15 |
| Febalance, ≈30 % | balance | — |
1.4971-SA — frequently asked
What is 1.4971-SA used for?
1.4971-SA is typically used for gas turbine casings, furnace fixtures and high-temperature fasteners. In short: cobalt austenitic, 900 °C; highest hot strength on file; superalloy-like machining.
What is the yield strength of 1.4971-SA?
1.4971-SA has a typical yield strength of 400 MPa (58 ksi) and a tensile strength of 815 MPa (118 ksi) — stronger than 57% of stainless steel grades. Strength varies by condition: see the 5 listed tempers.
Is 1.4971-SA easy to machine?
Not especially — machinability is rated poor (25/100, worse than 88% of stainless steel grades). Treat as a superalloy: rigid setups, sharp positive-rake carbide or ceramic tooling, low surface speed with heavy feed, flood coolant, and avoid dwelling — the alloy work-hardens rapidly and galls.
Can 1.4971-SA be welded?
Yes — weldability is rated good (60/100). GTAW/GMAW with matching N-155 (or Haynes 556/inconel-type) filler; clean joints, low heat input, no preheat needed, and re-solution treat heavily welded assemblies to restore creep properties.
What surface finishes work on 1.4971-SA?
Pickle/passivate or bead blast after hot working; not anodizable — use aluminide, MCrAlY or ceramic thermal-barrier coatings for the hottest oxidation/sulfidation duty.
Can 1.4971-SA be formed, bent or molded?
Hot work at 1050–1180 °C and finish above ~950 °C; cold forming needs 2–3× the force of 304 with frequent 1175 °C intermediate anneals.
What is the maximum service temperature of 1.4971-SA?
1.4971-SA is rated for continuous use to about 900°C (1,652 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 1.4971-SA and 1.4971-CD?
SA is the default condition — standard stocked condition for sheet, bar and forgings: maximum ductility and creep-rupture performance for long-term high-temperature service. CD: cold-finished bar and fastener wire: raised yield strength and better surface/tolerance, but residual cold work limits long-term use above ~600 °C. Yield strength is 400 MPa in SA versus 750 MPa in CD.
Sources
- DIN 17240 — Heat-resistant steels for bolts and nuts (X12CrCoNi21-20, 1.4971) — DIN (1976)
- AMS 5769 / AMS 5794 — Alloy N-155 (UNS R30155) bar, sheet and strip — SAE International (2019)
- ASM Specialty Handbook: Heat-Resistant Materials — ASM International (1997)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- Multimet / N-155 (R30155) alloy datasheet — Haynes International / specialty alloy producers (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.