Stainless Steel EN 1.4852 · finish state · default condition
Stainless Steel EN 1.4852 AC-CENT
Properties of the AC-CENT condition, compared with the other EN 1.4852 tempers.
Standard supply condition for pyrolysis/reformer radiant tubes — fine columnar structure, best creep-rupture life.
What is EN 1.4852 AC-CENT?
EN 1.4852 AC-CENT is EN 1.4852 supplied in the AC-CENT condition — standard supply condition for pyrolysis/reformer radiant tubes — fine columnar structure, best creep-rupture life. EN 1.4852 AC-CENT has a yield strength of 270 MPa (39.2 ksi) and a tensile strength of 500 MPa (72.5 ksi) — weaker than 79% of stainless steel grades. Elongation at break is 11% and the elastic modulus is 180 GPa (26.1 Msi). EN 1.4852 AC-CENT has a density of 7.9 g/cm³ (0.285 lb/in³), heavier than 67% of stainless steel grades. It melts at 1,330°C (2,426 °F).
Advantages
- High service temperature — 1,100°C (2,012 °F), better than 96% of stainless steel grades
Limitations
- Limited formability — 5/100, worse than 99% of stainless steel grades
- Hard to polish — 40/100, worse than 99% of stainless steel grades
- Limited ductility — 11%, worse than 96% of stainless steel grades
- High embodied carbon — 7 kg CO₂/kg, worse than 96% of stainless steel grades
- Difficult to machine — 22/100, worse than 95% of stainless steel grades
EN 1.4852 AC-CENT properties
Typical room-temperature values for EN 1.4852 AC-CENT — 11 properties are specific to this condition; the rest are grade-level values shared by every EN 1.4852 temper. Each bar shows where the value sits among the stainless steel grades in FabDigit's library — further right is higher.
Physical3
EN 1.4852 AC-CENT has a density of 7.9 g/cm³ (0.285 lb/in³), heavier than 67% of stainless steel grades. It melts at 1,330°C (2,426 °F).
Mechanical13
EN 1.4852 AC-CENT has a yield strength of 270 MPa (39.2 ksi) and a tensile strength of 500 MPa (72.5 ksi) — weaker than 79% of stainless steel grades. Elongation at break is 11% and the elastic modulus is 180 GPa (26.1 Msi).
Thermal5
EN 1.4852 AC-CENT is rated for continuous service to 1,100°C (2,012 °F). It conducts heat at 13 W/m·K (7.51 BTU/hr·ft·°F), worse than 85% of stainless steel grades. Thermal expansion is 15.5 µm/m·K (8.61 µin/in·°F).
Electrical3
EN 1.4852 AC-CENT conducts electricity at 1.7 % IACS, worse than 93% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (62/100), worse than 53% of stainless steel grades.
Sustainability4
Producing a kilogram of EN 1.4852 AC-CENT 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
EN 1.4852 AC-CENT's machinability is poor (22/100, worse than 95% of stainless steel grades); weldability fair (50/100); formability not recommended (5/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other EN 1.4852 tempers and conditions
EN 1.4852 is also supplied in 3 other conditions. The full side-by-side table is on the EN 1.4852 overview.
- AC-CENTDefaultStandard supply condition for pyrolysis/reformer radiant tubes — fine columnar structure, best creep-rupture life.270 MPa yield · 190 HB
- AgedReference condition for repair, re-weld and remaining-life assessment of used furnace tubes — carbide coarsening raises hardness and destroys room-temperature ductility.300 MPa yield · 220 HB
Working with EN 1.4852 AC-CENT
Is EN 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 EN 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 EN 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 EN 1.4852?
Shot blasting plus ID machining/honing; no plating or anodizing — the protective Cr₂O₃/SiO₂ scale forms in service.
EN 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 | — |
EN 1.4852 AC-CENT — frequently asked
What is EN 1.4852 AC-CENT used for?
EN 1.4852 AC-CENT 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 EN 1.4852 AC-CENT?
EN 1.4852 AC-CENT has a typical yield strength of 270 MPa (39.2 ksi) and a tensile strength of 500 MPa (72.5 ksi) — weaker than 79% of stainless steel grades. Strength varies by condition: see the 4 listed tempers.
Is EN 1.4852 AC-CENT easy to machine?
Not especially — machinability is rated poor (22/100, worse than 95% 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 EN 1.4852 AC-CENT be welded?
With care — weldability is rated fair (50/100). 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 EN 1.4852 AC-CENT?
Shot blasting plus ID machining/honing; no plating or anodizing — the protective Cr₂O₃/SiO₂ scale forms in service.
Can EN 1.4852 AC-CENT 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 EN 1.4852 AC-CENT?
EN 1.4852 AC-CENT 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 EN 1.4852 AC-CENT and EN 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.