Stainless Steel 1.4980-ST (Solution annealed)
Heat-treated state
EN 1.4980 · UNS S66286 · also A-286
Softest supply condition for forming, deep drawing, machining of complex parts and welding before final aging.
Values for the ST condition
Other 1.4980 tempers and conditions
1.4980 is listed in 5 conditions; see the grade overview at 1.4980.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
STThis page Solution annealed | Softest supply condition for forming, deep drawing, machining of complex parts and welding before final aging. | 310 | 690 | 45 | 170 HB | — |
Cold drawn | Cold-drawn bar or wire supplied for cold-heading and secondary forming, or as feedstock to be aged after fabrication. | 690 | 900 | 20 | 25 HRC | 1.9 % IACS |
STADefault Solution treated and aged | Standard commercial condition for bar, forgings and fasteners: ~1000 MPa UTS with good ductility and creep strength to 700 °C. | 700 | 1,000 | 25 | 31 HRC | — |
Solution treated 900 °C + aged 720 °C/16 h | Finer-grain, higher-yield cycle for high-temperature bolting and turbine fasteners where notch strength matters more than creep-rupture ductility. | 760 | 1,035 | 20 | 34 HRC | — |
Cold worked then aged | Choose for 1200 MPa-class bolts, springs and studs where the extra strength from cold work plus γ′ aging is needed at moderate temperature. | 1,000 | 1,240 | 12 | 38 HRC | — |
What is 1.4980-ST?
1.4980-ST is 1.4980 heat treated to ST — softest supply condition for forming, deep drawing, machining of complex parts and welding before final aging. 1.4980-ST has a yield strength of 310 MPa (45 ksi) and a tensile strength of 690 MPa (100 ksi) — weaker than 63% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 201 GPa (29.2 Msi). 1.4980-ST has a density of 7.92 g/cm³ (0.286 lb/in³), heavier than 77% of stainless steel grades. It melts at 1,370°C (2,498 °F). STA is the default condition FabDigit quotes; ST is available on request or by drawing note.
Advantages
- Ductile — tolerates forming and impact — 45%, better than 76% of stainless steel grades
Limitations
- Poor heat conductor — 12.6 W/m·K (7.28 BTU/hr·ft·°F), worse than 88% of stainless steel grades
- High embodied carbon — 5.8 kg CO₂/kg, worse than 86% of stainless steel grades
- Low electrical conductivity — 1.9 % IACS, worse than 84% of stainless steel grades
1.4980-ST properties
Typical room-temperature values for 1.4980-ST; 16 are specific to this condition. Other listed values are 1.4980 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
1.4980-ST has a density of 7.92 g/cm³ (0.286 lb/in³), heavier than 77% of stainless steel grades. It melts at 1,370°C (2,498 °F).
Mechanical16
1.4980-ST has a yield strength of 310 MPa (45 ksi) and a tensile strength of 690 MPa (100 ksi) — weaker than 63% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 201 GPa (29.2 Msi).
Thermal6
1.4980-ST is rated for continuous service to 600°C (1,112 °F). It conducts heat at 12.6 W/m·K (7.28 BTU/hr·ft·°F), worse than 88% of stainless steel grades. Thermal expansion is 16.4 µm/m·K (9.11 µin/in·°F).
Electrical3
1.4980-ST conducts electricity at 1.9 % IACS, worse than 84% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (60/100), worse than 58% of stainless steel grades.
Sustainability4
Producing a kilogram of 1.4980-ST takes about 80 MJ of energy and emits 5.8 kg of CO₂ — more than 89% of stainless steel grades. Typical recycled content is 35%.
Manufacturability7
1.4980-ST's machinability is poor (28/100, worse than 79% of stainless steel grades); weldability good (60/100); formability good (62/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 1.4980-ST
Is 1.4980 easy to machine?
Machine in the solution-treated state when possible; rigid setups, positive-rake carbide or ceramic tooling, low speed (15–25 m/min in STA), heavy feed and flood coolant to avoid work-hardened glaze and rapid notch wear.
Can 1.4980 be welded?
GTAW/EBW with matching or Inconel 82/718 filler in the solution condition, low heat input and no preheat; re-solution treat and age after welding to avoid strain-age (post-weld heat treatment) cracking in restrained joints.
Can 1.4980 be formed, bent or molded?
Cold form or cold head in the solution-treated condition (high work-hardening rate — allow extra power and intermediate anneals); hot work 1100–1150 °C, finish above 950 °C, then solution treat and age.
What surface finishes work on 1.4980?
Passivate per AMS 2700 after machining; electropolish or shot peen for fatigue-critical parts; threaded fasteners are usually silver-plated or coated with dry-film lubricant to prevent galling and high-temperature seizure.
1.4980 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 | 0.03 – 0.08 | 0.05 |
| Si | ≤ 1 | 0.4 |
| Mn | ≤ 2 | 1.3 |
| P | ≤ 0.04 | — |
| S | ≤ 0.03 | — |
| Cr | 13.5 – 16 | 14.8 |
| Ni | 24 – 27 | 25.5 |
| Mo | 1 – 1.5 | 1.25 |
| Tiγ′ Ni₃(Ti,Al) former | 1.9 – 2.35 | 2.1 |
| V | 0.1 – 0.5 | 0.3 |
| Al | ≤ 0.35 | 0.2 |
| Bgrain-boundary strengthener | 0 – 0.01 | 0.01 |
| Febalance, ~53–55 % | balance | — |
1.4980-ST — frequently asked
What is 1.4980-ST used for?
1.4980-ST is typically used for jet engine fasteners and rings, turbocharger hardware, high-temperature bolting and aerospace structural parts. In short: A-286 under EN number; strength to 700 °C; hardest-machining PH stainless.
What is the yield strength of 1.4980-ST?
1.4980-ST has a typical yield strength of 310 MPa (45 ksi) and a tensile strength of 690 MPa (100 ksi) — weaker than 63% of stainless steel grades. Strength varies by condition: see the 5 listed tempers.
Is 1.4980-ST easy to machine?
Not especially — machinability is rated poor (28/100, worse than 79% of stainless steel grades). Machine in the solution-treated state when possible; rigid setups, positive-rake carbide or ceramic tooling, low speed (15–25 m/min in STA), heavy feed and flood coolant to avoid work-hardened glaze and rapid notch wear.
Can 1.4980-ST be welded?
Yes — weldability is rated good (60/100). GTAW/EBW with matching or Inconel 82/718 filler in the solution condition, low heat input and no preheat; re-solution treat and age after welding to avoid strain-age (post-weld heat treatment) cracking in restrained joints.
What surface finishes work on 1.4980-ST?
Passivate per AMS 2700 after machining; electropolish or shot peen for fatigue-critical parts; threaded fasteners are usually silver-plated or coated with dry-film lubricant to prevent galling and high-temperature seizure.
Can 1.4980-ST be formed, bent or molded?
Cold form or cold head in the solution-treated condition (high work-hardening rate — allow extra power and intermediate anneals); hot work 1100–1150 °C, finish above 950 °C, then solution treat and age.
What is the maximum service temperature of 1.4980-ST?
1.4980-ST is rated for continuous use to about 600°C (1,112 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 1.4980-STA and 1.4980-ST?
STA is the default condition — standard commercial condition for bar, forgings and fasteners: ~1000 MPa UTS with good ductility and creep strength to 700 °C. ST: softest supply condition for forming, deep drawing, machining of complex parts and welding before final aging. Yield strength is 700 MPa in STA versus 310 MPa in ST.
Sources
- EN 10269 — Steels and nickel alloys for fasteners with specified elevated/low temperature properties (X6NiCrTiMoVB25-15-2, 1.4980) — CEN (2013)
- ASTM A453/A453M — Bolting with Yield Strength 50–120 ksi, Grade 660 Classes A/B/C/D — ASTM (2020)
- AMS 5731 / AMS 5732 / AMS 5737 — Alloy bars, forgings and rings, Fe-25Ni-15Cr-2Ti (A-286) — SAE International (2019)
- AMS 5525 — Steel sheet, strip and plate, corrosion and heat resistant 15Cr-26Ni-1.3Mo-2.1Ti — SAE International (2018)
- ASM Specialty Handbook: Heat-Resistant Materials (A-286 data) — ASM International (1997)
- Metallic Materials Properties Development and Standardization (MMPDS) — A-286 chapter — FAA/Battelle (2023)
- GB/T 14992 / HB 5199 — GH2132 (2019)
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.