Stainless Steel 1.4848
EN 1.4848 · UNS J94224 · ASTM A297 Grade HK
25Cr-20Ni fully austenitic cast heat-resistant steel (HK-type) with excellent high-temperature strength and oxidation resistance, widely used for radiant tube and pyrolysis furnace components up to ~1100 °C.
Reference datasheet — 1.4848 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the F condition
1.4848 tempers and conditions
1.4848 is supplied in 3 conditions, soft to hard. F is the default FabDigit quotes; the values on this page are for it.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution/diffusion annealed ~1050–1100 °C, rapid cool | Optional treatment to homogenise the carbide network and improve room-temperature ductility/toughness before machining or welding of critical castings. | 260 | 500 | 20 | 175 HB | 1.9 % IACS |
Stress relieved | Use for large or welded/repair-welded castings to relieve residual stress and reduce distortion on first heat-up; strength essentially unchanged. | 275 | 525 | 13 | 190 HB | 1.9 % IACS |
FDefault As fabricated | Standard supply condition for furnace hardware, fixtures, grate bars and shaped castings; no heat treatment applied. | 280 | 530 | 14 | 190 HB | 1.9 % IACS |
Supply forms, finishes and certifications
Ways 1.4848 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
CC | Centrifugally cast tube | Surface finish |
What is 1.4848?
25Cr-20Ni fully austenitic cast heat-resistant steel (HK-type) with excellent high-temperature strength and oxidation resistance, widely used for radiant tube and pyrolysis furnace components up to ~1100 °C. 1.4848 has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 65% of stainless steel grades. It melts at 1,370°C (2,498 °F). 1.4848 has a yield strength of 280 MPa (40.6 ksi) and a tensile strength of 530 MPa (76.9 ksi) — weaker than 75% of stainless steel grades. Elongation at break is 14% and the elastic modulus is 185 GPa (26.8 Msi).
What is 1.4848 used for?
- ethylene cracking furnace tubes
- reformer tubes
- heat-treat baskets and trays
- muffle furnace linings
- petrochemical furnace hardware
Advantages
- High service temperature — 1,100°C (2,012 °F), better than 96% of stainless steel grades
Limitations
- Limited formability — 8/100, worse than 97% of stainless steel grades
- Hard to polish — 45/100, worse than 96% of stainless steel grades
- Limited ductility — 14%, 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
1.4848 properties
Typical room-temperature values for 1.4848-F; bars are the position among stainless steel grades.
Physical3
1.4848 has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 65% of stainless steel grades. It melts at 1,370°C (2,498 °F).
Mechanical14
1.4848 has a yield strength of 280 MPa (40.6 ksi) and a tensile strength of 530 MPa (76.9 ksi) — weaker than 75% of stainless steel grades. Elongation at break is 14% and the elastic modulus is 185 GPa (26.8 Msi).
Thermal6
1.4848 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 µm/m·K (8.33 µin/in·°F).
Electrical3
1.4848 conducts electricity at 1.9 % IACS, worse than 84% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (58/100), worse than 62% of stainless steel grades.
Sustainability4
Producing a kilogram of 1.4848 takes about 62 MJ of energy and emits 4.6 kg of CO₂ — more than 75% of stainless steel grades. Typical recycled content is 75%.
Manufacturability8
1.4848's machinability is poor (25/100, worse than 88% of stainless steel grades); weldability fair (45/100); formability not recommended (8/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the stainless steel family
Yield strength against density for every stainless steel grade FabDigit runs. 1.4848 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 1.4848
Is 1.4848 easy to machine?
Machine like a sensitised high-carbon austenitic: rigid setup, sharp carbide or ceramic tooling, low speed with heavy positive feed, flood coolant — the primary carbide network is abrasive and the matrix work-hardens badly; grinding is often preferred for finishing.
Can 1.4848 be welded?
Weld with matching HK/ER310 or 25Cr-20Ni filler, low heat input and no preheat needed for new castings; service-aged parts must be locally solution/stress-relief annealed before repair welding to avoid carbide-embrittlement cracking.
Can 1.4848 be formed, bent or molded?
Supplied only as cast (static sand/shell or centrifugal); allow generous risering for the high solidification shrinkage, avoid sharp section changes to limit hot tearing, and machine after cooling — no cold forming.
1.4848 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 |
|---|---|---|
| CEN 10295 GX40CrNiSi25-20; ASTM A297 HK allows 0.20–0.60, HK40 = 0.35–0.45 | 0.3 – 0.5 | 0.4 |
| SiA297 HK: max 2.00 | 1 – 2.5 | 1.6 |
| Mn | ≤ 2 | 1.2 |
| CrA297 HK: 24.0–28.0 | 24 – 27 | 25.5 |
| NiA297 HK: 18.0–22.0 | 19 – 22 | 20.5 |
| Moresidual only | ≤ 0.5 | — |
| P | ≤ 0.04 | — |
| SA297: max 0.04 | ≤ 0.03 | — |
| Fe | balance | — |
What surface finishes work on 1.4848?
Normally left as-cast, shot-blasted or pickled; no coating is needed for oxidation service since the Cr-Si oxide scale is protective, and aluminising can be used where sulphidation or carburisation is severe.
Surface treatments FabDigit runs on stainless steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Passivation
Organic Coating
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Stainless Steel 1.4848 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- J94224
- ASTM
- A297 Grade HK
- EN / DIN / Werkstoff-Nr.
- GX40CrNiSi25-20
- Also called
- HK40
How much does 1.4848 cost?
1.4848 is a premium-cost stainless steel ($$$), cheaper than about 51% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
1.4848 — frequently asked
What is 1.4848 used for?
1.4848 is typically used for ethylene cracking furnace tubes, reformer tubes, heat-treat baskets and trays, muffle furnace linings and petrochemical furnace hardware. In short: standard HK cast grade; 1100 °C oxidation service; difficult to machine.
What is the yield strength of 1.4848?
1.4848 has a typical yield strength of 280 MPa (40.6 ksi) and a tensile strength of 530 MPa (76.9 ksi) — weaker than 75% of stainless steel grades. Strength varies by condition: see the 3 listed tempers.
Is 1.4848 easy to machine?
Not especially — machinability is rated poor (25/100, worse than 88% of stainless steel grades). Machine like a sensitised high-carbon austenitic: rigid setup, sharp carbide or ceramic tooling, low speed with heavy positive feed, flood coolant — the primary carbide network is abrasive and the matrix work-hardens badly; grinding is often preferred for finishing.
Can 1.4848 be welded?
With care — weldability is rated fair (45/100). Weld with matching HK/ER310 or 25Cr-20Ni filler, low heat input and no preheat needed for new castings; service-aged parts must be locally solution/stress-relief annealed before repair welding to avoid carbide-embrittlement cracking.
What surface finishes work on 1.4848?
Normally left as-cast, shot-blasted or pickled; no coating is needed for oxidation service since the Cr-Si oxide scale is protective, and aluminising can be used where sulphidation or carburisation is severe.
Can 1.4848 be formed, bent or molded?
Supplied only as cast (static sand/shell or centrifugal); allow generous risering for the high solidification shrinkage, avoid sharp section changes to limit hot tearing, and machine after cooling — no cold forming.
What is the maximum service temperature of 1.4848?
1.4848 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 1.4848-F and 1.4848-SA?
F is the default condition — standard supply condition for furnace hardware, fixtures, grate bars and shaped castings; no heat treatment applied. SA: optional treatment to homogenise the carbide network and improve room-temperature ductility/toughness before machining or welding of critical castings. Yield strength is 280 MPa in F versus 260 MPa in SA.
How much does 1.4848 cost?
1.4848 is a premium-cost stainless steel ($$$), cheaper than about 51% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- ASTM A297/A297M — Steel Castings, Iron-Chromium and Iron-Chromium-Nickel, Heat Resistant, for General Application (Grade HK) — ASTM International (2019)
- ASTM A608/A608M — Centrifugally Cast Iron-Chromium-Nickel High-Alloy Tubing for Pressure Application at High Temperatures (HK40) — ASTM International (2018)
- EN 10295 — Heat resistant steel castings (GX40CrNiSi25-20, 1.4848) — CEN (2002)
- GB/T 8492 — (ZG40Cr25Ni20) — SAC (2014)
- ASM Handbook Vol. 1 — Heat-Resistant Castings; Vol. 15 Casting — ASM International (1990)
- Heat-resistant cast alloy datasheets for HK40 / 1.4848 (furnace hardware and centrifugal tube producers) — various foundries (2023)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.