Stainless Steel 1.4825
EN 1.4825
1.4825 (GX25CrNiSi18-9, ASTM A297 HF) is a silicon-enhanced 18Cr-9Ni cast heat-resistant austenitic steel, supplied as sand castings in as-cast (AC), solution-annealed (SA) or stress-relieved (SR) condition.
Reference datasheet — 1.4825 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 AC condition
1.4825 tempers and conditions
1.4825 is supplied in 3 conditions, soft to hard. AC 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 annealed ~1050–1100 °C, rapid cooled | Chosen when maximum room-temperature ductility/toughness or a more homogeneous, less carbide-networked structure is needed before machining or welding. | 230 | 490 | 25 | 155 HB | 2.2 % IACS |
Stress relieved | Use after heavy welding or for dimensionally critical castings to reduce residual stress without changing the as-cast strength level much. | 250 | 510 | 18 | 170 HB | 2.2 % IACS |
ACDefault Spheroidize annealed | Standard supply condition for furnace and exhaust hardware; heat-resistant castings normally go into service as-cast. | 260 | 520 | 18 | 175 HB | 2.2 % IACS |
What is 1.4825?
1.4825 (GX25CrNiSi18-9, ASTM A297 HF) is a silicon-enhanced 18Cr-9Ni cast heat-resistant austenitic steel, supplied as sand castings in as-cast (AC), solution-annealed (SA) or stress-relieved (SR) condition. Engineers specify it for furnace and exhaust hardware where oxidation resistance up to a 900 °C service limit matters more than strength: 260 MPa yield, 520 MPa tensile, 18 % elongation, 175 HB. The interdendritic carbide network makes it difficult to cut (machinability score 32) and it requires 309-type filler with post-weld stress relief or solution anneal. Where higher temperatures or higher chromium are needed, move to an HH/HK-type heat-resistant casting. 1.4825 has a density of 7.7 g/cm³ (0.278 lb/in³), lighter than 83% of stainless steel grades. It melts at 1,400°C (2,552 °F). 1.4825 has a yield strength of 260 MPa (37.7 ksi) and a tensile strength of 520 MPa (75.4 ksi) — weaker than 84% of stainless steel grades. Elongation at break is 18% and the elastic modulus is 185 GPa (26.8 Msi).
What is 1.4825 used for?
- exhaust manifolds
- furnace fixtures
- heat-treatment fittings
Advantages
- High service temperature — 900°C (1,652 °F), better than 85% of stainless steel grades
Limitations
- Hard to polish — 45/100, worse than 96% of stainless steel grades
- Limited formability — 15/100, worse than 91% of stainless steel grades
- Low fracture toughness — 60 MPa·√m (54.6 ksi·√in), worse than 88% of stainless steel grades
- Low strength — 260 MPa (37.7 ksi), worse than 84% of stainless steel grades
- Limited ductility — 18%, worse than 83% of stainless steel grades
1.4825 properties
Typical room-temperature values for 1.4825-AC; bars are the position among stainless steel grades.
Physical3
1.4825 has a density of 7.7 g/cm³ (0.278 lb/in³), lighter than 83% of stainless steel grades. It melts at 1,400°C (2,552 °F).
Mechanical16
1.4825 has a yield strength of 260 MPa (37.7 ksi) and a tensile strength of 520 MPa (75.4 ksi) — weaker than 84% of stainless steel grades. Elongation at break is 18% and the elastic modulus is 185 GPa (26.8 Msi).
Thermal6
1.4825 is rated for continuous service to 900°C (1,652 °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 17 µm/m·K (9.44 µin/in·°F).
Electrical3
1.4825 conducts electricity at 2.2 % IACS, worse than 61% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (55/100), worse than 71% of stainless steel grades.
Sustainability4
Producing a kilogram of 1.4825 takes about 53 MJ of energy and emits 4.5 kg of CO₂ — less than 67% of stainless steel grades. Typical recycled content is 70%.
Manufacturability8
1.4825's machinability is poor (32/100, worse than 62% of stainless steel grades); weldability fair (45/100); formability poor (15/100).
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. 1.4825 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 1.4825
Is 1.4825 easy to machine?
Machine with rigid setups, sharp carbide (K/C-grade) tooling, low speed and heavy positive feed to cut through the interdendritic carbide network; flood coolant and avoid dwelling to limit work hardening.
Can 1.4825 be welded?
Weldable by SMAW/GTAW with 309/matching high-Si filler; preheat 150–250 °C for heavy sections, keep interpass low, and stress relieve or solution anneal afterwards to reduce hot-cracking and carbide-related embrittlement.
Can 1.4825 be formed, bent or molded?
Sand-cast only — no cold forming; design generous fillets and uniform wall thickness, use large risers and account for ~2 % solidification shrinkage plus high thermal expansion in fixture design.
1.4825 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 |
|---|---|---|
| Chigh C for creep/strength; ASTM A297 HF allows 0.20–0.40 | 0.15 – 0.35 | 0.25 |
| Sikey oxidation-resistance addition (A297 HF: Si ≤ 2.00) | 1 – 2.5 | 1.8 |
| MnA297 HF: ≤ 2.00 | ≤ 1.5 | 1 |
| CrA297 HF: 18.0–23.0 | 17 – 19 | 18 |
| NiA297 HF: 8.0–12.0 | 8 – 10 | 9 |
| P | ≤ 0.05 | |
| S | ≤ 0.03 | |
| Moresidual only, not intentionally added | ≤ 0.5 | |
| Fe | balance |
What surface finishes work on 1.4825?
Shot-blast and pickle/passivate scale after casting or heat treatment; no anodizing — for severe service use aluminizing or a ceramic/alumina wash coating.
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 1.4825 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- EN / DIN / Werkstoff-Nr.
- GX25CrNiSi18-9
- Similar grades
- A297 HF
How much does 1.4825 cost?
1.4825 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.
1.4825 — frequently asked
What is 1.4825 used for?
1.4825 is typically used for exhaust manifolds, furnace fixtures and heat-treatment fittings. In short: cast heat-resistant 18-9; oxidation resistance to 900 °C; sand-cast forms only.
What is the yield strength of 1.4825?
1.4825 has a typical yield strength of 260 MPa (37.7 ksi) and a tensile strength of 520 MPa (75.4 ksi) — weaker than 84% of stainless steel grades. Strength varies by condition: see the 3 listed tempers.
Is 1.4825 easy to machine?
Not especially — machinability is rated poor (32/100, worse than 62% of stainless steel grades). Machine with rigid setups, sharp carbide (K/C-grade) tooling, low speed and heavy positive feed to cut through the interdendritic carbide network; flood coolant and avoid dwelling to limit work hardening.
Can 1.4825 be welded?
With care — weldability is rated fair (45/100). Weldable by SMAW/GTAW with 309/matching high-Si filler; preheat 150–250 °C for heavy sections, keep interpass low, and stress relieve or solution anneal afterwards to reduce hot-cracking and carbide-related embrittlement.
What surface finishes work on 1.4825?
Shot-blast and pickle/passivate scale after casting or heat treatment; no anodizing — for severe service use aluminizing or a ceramic/alumina wash coating.
Can 1.4825 be formed, bent or molded?
Sand-cast only — no cold forming; design generous fillets and uniform wall thickness, use large risers and account for ~2 % solidification shrinkage plus high thermal expansion in fixture design.
What is the maximum service temperature of 1.4825?
1.4825 is rated for continuous use to about 900°C (1,652 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 1.4825-AC and 1.4825-SA?
AC is the default condition — standard supply condition for furnace and exhaust hardware; heat-resistant castings normally go into service as-cast. SA: chosen when maximum room-temperature ductility/toughness or a more homogeneous, less carbide-networked structure is needed before machining or welding. Yield strength is 260 MPa in AC versus 230 MPa in SA.
How much does 1.4825 cost?
1.4825 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
- EN 10295 — Heat resistant steel castings — CEN (2002)
- ASTM A297/A297M — Steel Castings, Iron-Chromium and Iron-Chromium-Nickel, Heat Resistant, for General Application (grade HF) — ASTM (2019)
- DIN 17465 — Heat resisting steel castings (GX25CrNiSi18-9) — DIN (1985)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels, and High-Performance Alloys (heat-resistant castings) — ASM International (1990)
- ASM Handbook Vol. 13B — Corrosion: Materials (high-temperature oxidation of cast Cr-Ni alloys) — ASM International (2005)
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.