Stainless Steel 1.4852 Aged
Heat-treated state
EN 1.4852 · UNS J95709 · ASTM A297 Grade HP-Nb
Aged = thermally aged / service-exposed
Reference condition for repair, re-weld and remaining-life assessment of used furnace tubes — carbide coarsening raises hardness and destroys room-temperature ductility.
Values for the Aged condition
Other 1.4852 tempers and conditions
1.4852 is listed in 3 conditions; see the grade overview at 1.4852.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
AC-CENTDefault As-cast, centrifugally cast tube | Standard supply condition for pyrolysis/reformer radiant tubes — fine columnar structure, best creep-rupture life. | 270 | 500 | 11 | 190 HB | — |
HP-Nb micro-alloyed | Pick when maximum creep-rupture life and carburization/coking resistance are required for long-campaign ethylene coils. | 285 | 520 | 10 | 195 HB | 1.7 % IACS |
AgedThis page Thermally aged / service-exposed | Reference condition for repair, re-weld and remaining-life assessment of used furnace tubes — carbide coarsening raises hardness and destroys room-temperature ductility. | 300 | 470 | 3 | 220 HB | 1.8 % IACS |
What is 1.4852 Aged?
1.4852 Aged is 1.4852 heat treated to Aged — reference condition for repair, re-weld and remaining-life assessment of used furnace tubes — carbide coarsening raises hardness and destroys room-temperature ductility. 1.4852 Aged has a yield strength of 300 MPa (43.5 ksi) and a tensile strength of 470 MPa (68.2 ksi) — weaker than 68% of stainless steel grades. Elongation at break is 3% and the elastic modulus is 180 GPa (26.1 Msi). 1.4852 Aged has a density of 7.9 g/cm³ (0.285 lb/in³), heavier than 68% of stainless steel grades. It melts at 1,330°C (2,426 °F). AC-CENT is the default condition FabDigit quotes; Aged is available on request or by drawing note.
Advantages
- High service temperature — 1,100°C (2,012 °F), better than 96% of stainless steel grades
Limitations
- Limited ductility — 3%, worse than 100% of stainless steel grades
- Difficult to machine — 15/100, worse than 100% of stainless steel grades
- Limited formability — 2/100, worse than 100% of stainless steel grades
- Hard to polish — 40/100, worse than 99% of stainless steel grades
- High embodied carbon — 7 kg CO₂/kg, worse than 96% of stainless steel grades
1.4852 Aged properties
Typical room-temperature values for 1.4852 Aged; 22 are specific to this condition. Other listed values are 1.4852 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
1.4852 Aged has a density of 7.9 g/cm³ (0.285 lb/in³), heavier than 68% of stainless steel grades. It melts at 1,330°C (2,426 °F).
Mechanical13
1.4852 Aged has a yield strength of 300 MPa (43.5 ksi) and a tensile strength of 470 MPa (68.2 ksi) — weaker than 68% of stainless steel grades. Elongation at break is 3% and the elastic modulus is 180 GPa (26.1 Msi).
Thermal5
1.4852 Aged is rated for continuous service to 1,100°C (2,012 °F). It conducts heat at 14 W/m·K (8.09 BTU/hr·ft·°F), worse than 80% of stainless steel grades. Thermal expansion is 15.5 µm/m·K (8.61 µin/in·°F).
Electrical3
1.4852 Aged conducts electricity at 1.8 % IACS, worse than 87% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (56/100), worse than 66% of stainless steel grades.
Sustainability4
Producing a kilogram of 1.4852 Aged takes about 90 MJ of energy and emits 7 kg of CO₂ — more than 94% of stainless steel grades. Typical recycled content is 60%.
Manufacturability8
1.4852 Aged's machinability is poor (15/100, worse than 100% of stainless steel grades); weldability poor (30/100); formability not recommended (2/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 1.4852 Aged
Is 1.4852 easy to machine?
Hard interdendritic carbides and severe work hardening — use rigid setups, carbide/ceramic inserts, low speed with heavy positive feed and flood coolant; ID boring of centrifugal tubes is the normal finishing operation.
Can 1.4852 be welded?
GTAW/SMAW with matching HP-Nb filler, preheat generally not required but interpass temperature must be controlled; aged or carburized ex-service tubes need buttering/decarburized-layer removal to avoid hot cracking.
Can 1.4852 be formed, bent or molded?
Cast only (centrifugal for tubes, sand/investment for fittings); no cold or hot forming — geometry is achieved in the mould and by machining.
What surface finishes work on 1.4852?
Shot blasting plus ID machining/honing; no plating or anodizing — the protective Cr₂O₃/SiO₂ scale forms in service.
1.4852 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 |
|---|---|---|
| CASTM A297 HP allows up to 0.75 % | 0.35 – 0.45 | 0.4 |
| Siraises carburization resistance | 1 – 2.5 | 1.6 |
| Mn | ≤ 2 | 1 |
| P | ≤ 0.04 | — |
| S | ≤ 0.03 | — |
| Cr | 24 – 27 | 25.5 |
| Ni | 33 – 36 | 34.5 |
| Nbprimary MC carbide former, creep strengthening | 0.8 – 1.8 | 1.3 |
| Fe | balance | — |
1.4852 Aged — frequently asked
What is 1.4852 Aged used for?
1.4852 Aged is typically used for ethylene furnace radiant tubes, return bends and fittings for cracking furnaces and high-temperature process piping supports. In short: highest creep strength cast; carburization-resistant HP-Nb; 1100 °C tube grade.
What is the yield strength of 1.4852 Aged?
1.4852 Aged has a typical yield strength of 300 MPa (43.5 ksi) and a tensile strength of 470 MPa (68.2 ksi) — weaker than 68% of stainless steel grades. Strength varies by condition: see the 3 listed tempers.
Is 1.4852 Aged easy to machine?
Not especially — machinability is rated poor (15/100, worse than 100% of stainless steel grades). Hard interdendritic carbides and severe work hardening — use rigid setups, carbide/ceramic inserts, low speed with heavy positive feed and flood coolant; ID boring of centrifugal tubes is the normal finishing operation.
Can 1.4852 Aged be welded?
Not readily — weldability is rated poor (30/100). GTAW/SMAW with matching HP-Nb filler, preheat generally not required but interpass temperature must be controlled; aged or carburized ex-service tubes need buttering/decarburized-layer removal to avoid hot cracking.
What surface finishes work on 1.4852 Aged?
Shot blasting plus ID machining/honing; no plating or anodizing — the protective Cr₂O₃/SiO₂ scale forms in service.
Can 1.4852 Aged be formed, bent or molded?
Cast only (centrifugal for tubes, sand/investment for fittings); no cold or hot forming — geometry is achieved in the mould and by machining.
What is the maximum service temperature of 1.4852 Aged?
1.4852 Aged is rated for continuous use to about 1,100°C (2,012 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 1.4852 AC-CENT and 1.4852 Aged?
AC-CENT is the default condition — standard supply condition for pyrolysis/reformer radiant tubes — fine columnar structure, best creep-rupture life. Aged: reference condition for repair, re-weld and remaining-life assessment of used furnace tubes — carbide coarsening raises hardness and destroys room-temperature ductility. Yield strength is 270 MPa in AC-CENT versus 300 MPa in Aged.
Sources
- EN 10295 — Heat resistant steel castings — CEN (2002)
- ASTM A297/A297M — Steel Castings, Iron-Chromium-Nickel, Heat Resistant, for General Application — ASTM (2019)
- ASTM A608/A608M — Centrifugally Cast Iron-Chromium-Nickel High-Alloy Tubing for Pressure Application at High Temperatures — ASTM (2018)
- Centralloy / HP-Nb furnace tube alloy data — Schmidt + Clemens (2021)
- Manaurite HP-type reformer and cracking tube alloys — Manoir Industries (2019)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels and High-Performance Alloys (heat-resistant castings) — ASM International (1990)
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.