Stainless Steel 1.4849 Aged
Heat-treated state
EN 1.4849
Aged = thermally aged / service exposed
Reference condition for integrity assessment of tubes after service: secondary carbide and G-phase precipitation embrittles the alloy at room temperature.
Values for the Aged condition
Other 1.4849 tempers and conditions
1.4849 is listed in 3 conditions; see the grade overview at 1.4849.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution annealed ~1150 °C, rapid cooled | Occasionally specified to dissolve part of the primary carbide network and restore ductility before heavy machining or weld repair of thick sections. | 235 | 470 | 15 | 165 HB | 1.7 % IACS |
Statically (sand) cast, as-cast | Choose for fittings, return bends, headers, tube supports and shaped parts that cannot be centrifugally cast; coarser grain and slightly lower ductility. | 240 | 460 | 8 | 175 HB | 1.7 % IACS |
AgedThis page Thermally aged / service exposed | Reference condition for integrity assessment of tubes after service: secondary carbide and G-phase precipitation embrittles the alloy at room temperature. | 290 | 500 | 3 | 17 HRC | 1.8 % IACS |
What is 1.4849 Aged?
1.4849 Aged is 1.4849 heat treated to Aged — reference condition for integrity assessment of tubes after service: secondary carbide and G-phase precipitation embrittles the alloy at room temperature. 1.4849 Aged has a yield strength of 290 MPa (42.1 ksi) and a tensile strength of 500 MPa (72.5 ksi) — weaker than 72% of stainless steel grades. Elongation at break is 3% and the elastic modulus is 172 GPa (24.9 Msi). 1.4849 Aged has a density of 7.9 g/cm³ (0.285 lb/in³), heavier than 68% of stainless steel grades. It melts at 1,320°C (2,408 °F).
Advantages
- High service temperature — 1,050°C (1,922 °F), better than 91% of stainless steel grades
Limitations
- Limited ductility — 3%, worse than 100% of stainless steel grades
- Difficult to machine — 12/100, worse than 100% of stainless steel grades
- Limited formability — 2/100, worse than 100% of stainless steel grades
- Low stiffness — 172 GPa (24.9 Msi), worse than 99% of stainless steel grades
- Hard to polish — 45/100, worse than 96% of stainless steel grades
1.4849 Aged properties
Typical room-temperature values for 1.4849 Aged; 22 are specific to this condition. Other listed values are 1.4849 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
1.4849 Aged has a density of 7.9 g/cm³ (0.285 lb/in³), heavier than 68% of stainless steel grades. It melts at 1,320°C (2,408 °F).
Mechanical12
1.4849 Aged has a yield strength of 290 MPa (42.1 ksi) and a tensile strength of 500 MPa (72.5 ksi) — weaker than 72% of stainless steel grades. Elongation at break is 3% and the elastic modulus is 172 GPa (24.9 Msi).
Thermal6
1.4849 Aged is rated for continuous service to 1,050°C (1,922 °F). It conducts heat at 14.5 W/m·K (8.38 BTU/hr·ft·°F), worse than 72% of stainless steel grades. Thermal expansion is 15 µm/m·K (8.33 µin/in·°F).
Electrical3
1.4849 Aged conducts electricity at 1.8 % IACS, worse than 87% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (60/100), worse than 58% of stainless steel grades.
Sustainability4
Producing a kilogram of 1.4849 Aged takes about 80 MJ of energy and emits 6.2 kg of CO₂ — more than 89% of stainless steel grades. Typical recycled content is 70%.
Manufacturability8
1.4849 Aged's machinability is not recommended (12/100, worse than 100% of stainless steel grades); weldability poor (25/100); formability not recommended (2/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 1.4849 Aged
Is 1.4849 easy to machine?
Machine with rigid setups, positive-rake carbide or ceramic inserts, low speed and heavy constant feed; the Nb/Cr carbide network is abrasive and the austenite work-hardens, so avoid dwelling and interrupted light cuts.
Can 1.4849 be welded?
Weld as-cast with matching 38-19Nb filler (GTAW root, SMAW/FCAW fill), low heat input, no preheat needed for new material; aged/service-exposed tubes need degreasing, decarburising burn-out or buttering plus a temper-bead/dilution-control procedure.
Can 1.4849 be formed, bent or molded?
Not cold formable — shape is fixed by centrifugal or static casting; keep uniform wall, generous fillets and a machining allowance on the bore for the columnar-grain layer.
What surface finishes work on 1.4849?
Normally supplied shot-blasted or machined bore/OD; no plating or anodising is used, and a protective Cr2O3/SiO2 scale is grown in service, so avoid chloride-bearing marking inks and grinding contamination from carbon steel.
1.4849 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 |
|---|---|---|
| Cprimary carbide former with Nb/Cr | 0.3 – 0.5 | 0.4 |
| Siimproves carburisation resistance | 1 – 2.5 | 1.7 |
| Mn | ≤ 1.5 | 1 |
| P | ≤ 0.04 | — |
| S | ≤ 0.03 | — |
| Cr | 18 – 21 | 19 |
| Ni | 36 – 39 | 38 |
| Nbstabilises carbides, raises creep strength | 1.2 – 1.8 | 1.5 |
| Fe | balance | — |
1.4849 Aged — frequently asked
What is 1.4849 Aged used for?
1.4849 Aged is typically used for ethylene cracking coil tubes, steam reformer tubes and petrochemical radiant furnace fittings. In short: high-Ni carburization resistance; centrifugal tube alloy; machinability score 20.
What is the yield strength of 1.4849 Aged?
1.4849 Aged has a typical yield strength of 290 MPa (42.1 ksi) and a tensile strength of 500 MPa (72.5 ksi) — weaker than 72% of stainless steel grades. Strength varies by condition: see the 3 listed tempers.
Is 1.4849 Aged easy to machine?
Not especially — machinability is rated not recommended (12/100, worse than 100% of stainless steel grades). Machine with rigid setups, positive-rake carbide or ceramic inserts, low speed and heavy constant feed; the Nb/Cr carbide network is abrasive and the austenite work-hardens, so avoid dwelling and interrupted light cuts.
Can 1.4849 Aged be welded?
Not readily — weldability is rated poor (25/100). Weld as-cast with matching 38-19Nb filler (GTAW root, SMAW/FCAW fill), low heat input, no preheat needed for new material; aged/service-exposed tubes need degreasing, decarburising burn-out or buttering plus a temper-bead/dilution-control procedure.
What surface finishes work on 1.4849 Aged?
Normally supplied shot-blasted or machined bore/OD; no plating or anodising is used, and a protective Cr2O3/SiO2 scale is grown in service, so avoid chloride-bearing marking inks and grinding contamination from carbon steel.
Can 1.4849 Aged be formed, bent or molded?
Not cold formable — shape is fixed by centrifugal or static casting; keep uniform wall, generous fillets and a machining allowance on the bore for the columnar-grain layer.
What is the maximum service temperature of 1.4849 Aged?
1.4849 Aged is rated for continuous use to about 1,050°C (1,922 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- EN 10295 — Heat resistant steel castings — CEN (2002)
- DIN 17465 — Heat resistant steel castings (superseded) — DIN (1989)
- ASM Handbook Vol.1 — Cast Heat-Resistant Steels (HK/HP/HT types) — ASM International (1990)
- ASM Handbook Vol.13B — Corrosion in Reforming and Pyrolysis Furnaces — ASM International (2005)
- Centrifugally cast reformer/ethylene tube alloy datasheets (1.4849 / HT-Nb class) — Heat-resistant casting producers (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.