1.4835 Forgings: X9CrNiSiNCe21-11-2 / UNS S30815 Heat-Resistant Stainless Steel
Open-die forged rings, seamless rolled rings, flanges, round bars, discs, sleeves, bushings, tube sheets, shafts and valve components in 1.4835, made to drawing by Jiangyin Jiangnan Metal Co., Ltd., an open-die forging factory in Jiangyin, Jiangsu, China.
Summary. 1.4835 (EN name X9CrNiSiNCe21-11-2, UNS S30815, cross-reference 253 MA) is a heat-resistant austenitic stainless steel with about 20-22 % Cr, 10-12 % Ni and 1.4-2.5 % Si, plus nitrogen and cerium additions. It is a lean-nickel grade: oxidation resistance in air up to about 1150 °C and high creep strength come from the silicon, nitrogen and rare-earth additions rather than from a high nickel content, which is why it costs less than 25Cr/20Ni steels and Alloy 800H in many furnace and flue-gas applications.
For forgings the grade is normally ordered as ASTM A182 Grade F45 (flanges, fittings and valve parts for high-temperature service) or ASTM A473 (general stainless forgings). Both require a minimum of 600 MPa tensile, 310 MPa yield, 40 % elongation and 50 % reduction of area in the solution-annealed condition.
Key data
- EN number
- 1.4835
- EN name
- X9CrNiSiNCe21-11-2
- UNS
- S30815
- ASTM forging
- A182 F45 / A473
- Structure
- Austenitic, non-hardenable
- Max. air service
- about 1150 °C
- Density
- 7.8 g/cm³
Forged product forms
- Forged and seamless rolled rings, retaining rings, valve seat rings
- Flanges, blind flanges, tube sheets, nozzles, manifolds
- Round bars, shafts, eccentric shafts, spindles, crankshafts
- Discs, blanks, hubs, gears, wheels, rolls
- Sleeves, bushings, hollow bars, forged pipe and tube blanks
- Valve bodies, blocks, stems and bonnets
Order and inspection
- Melting route: EAF + VOD, ESR available
- Solution annealed 1050-1150 °C, rapid cooled
- UT to EN 10228-4 for austenitic forgings, or ASTM A388
- PT, PMI, grain size, hardness, room and elevated temperature tensile testing
- Certification to EN 10204 3.1 or 3.2 (TUV, SGS, BV, Lloyd's)
1. Chemical composition of 1.4835 / UNS S30815
Composition limits differ between the European and American specifications, so the ordering specification should be stated on the enquiry. We melt and forge to whichever of the columns below the purchase order calls for.
| Element | EN 10095, 1.4835 / X9CrNiSiNCe21-11-2 | ASTM A182 F45 and A473, UNS S30815 | Typical mill analysis |
|---|---|---|---|
| C | 0.05-0.12 | 0.05-0.10 | 0.08 |
| Si | 1.40-2.50 | 1.40-2.00 | 1.6 |
| Mn | 1.00 max | 0.80 max | 0.8 max |
| P | 0.045 max | 0.040 max | 0.040 max |
| S | 0.015 max | 0.030 max | 0.030 max |
| Cr | 20.00-22.00 | 20.00-22.00 | 21 |
| Ni | 10.00-12.00 | 10.00-12.00 | 11 |
| N | 0.12-0.20 | 0.14-0.20 | 0.17 |
| Ce | 0.030-0.080 | 0.03-0.08 | 0.05 |
| Fe | Balance | ||
The cerium addition is normally made as mischmetal containing roughly 50 % Ce, so other rare-earth metals are present alongside the cerium.
2. Mechanical properties
| Property | ASTM A182 F45 / A473 (S30815) | EN 10095 (1.4835) |
|---|---|---|
| Tensile strength Rm | 87 ksi (600 MPa) min. | 650-850 MPa (94-123 ksi) |
| Yield strength Rp0.2 | 45 ksi (310 MPa) min. | 310 MPa (45 ksi) min. |
| Yield strength Rp1.0 | not specified | 350 MPa (51 ksi) min. |
| Elongation A (2 in. / 50 mm or 4D) | 40 % min. | 37-40 % min. |
| Reduction of area | 50 % min. | not specified |
| Hardness | not specified | about 190 HV, 210 HB max. |
| Temperature | Rp0.2, MPa | Rp1.0, MPa | Rm, MPa |
|---|---|---|---|
| 100 °C | 225 | 265 | 550 |
| 200 °C | 189 | 215 | 475 |
| 300 °C | 170 | 200 | 440 |
| 400 °C | 160 | 190 | 425 |
| 500 °C | 150 | 180 | 400 |
| 600 °C | 140 | 165 | 340 |
Creep and creep-rupture strength
Above about 550 °C the design of 1.4835 parts is governed by creep-rupture strength rather than by Rp0.2. Published mean values for tube, pipe, plate and bar are given below. They are indicative, and the applicable design code values always take precedence.
| Temperature | 10 000 h | 100 000 h |
|---|---|---|
| 600 °C | 138 | 82 |
| 700 °C | 62 | 33 |
| 800 °C | 27 | 15 |
| 900 °C | 13 | 7.5 |
| 1000 °C | 7.0 | 4.3 |
| 1100 °C | 4.3 | 2.6 |
3. Physical properties
| Property | Value |
|---|---|
| Density | 7.8 g/cm³ (7800 kg/m³, 0.28 lb/in³) |
| Modulus of elasticity at 20 °C | 200 GPa; 185 GPa at 200 °C; 155 GPa at 600 °C; 120 GPa at 1000 °C |
| Mean coefficient of thermal expansion | 17.0 x 10-6/°C (0-100 °C); 18.5 x 10-6 (0-600 °C); 19.5 x 10-6 (0-1000 °C) |
| Thermal conductivity | about 13-15 W/m·K at 20 °C, rising to about 29 W/m·K at 1000 °C |
| Specific heat capacity (0-100 °C) | about 490-500 J/kg·K |
| Electrical resistivity at 20 °C | about 0.84-0.85 µΩ·m |
| Relative magnetic permeability | about 1.003, practically non-magnetic when annealed |
4. High-temperature behaviour
Oxidation in air
1.4835 forms a thin, highly adherent and elastic chromium-oxide scale, so it performs well under cyclic heating as well as under isothermal conditions. The service temperature in air should not exceed about 1150 °C. Isothermal exposure at 1150 °C for 100 h corresponds to roughly 0.3 mm per year of attack and 1000 h to roughly 0.2 mm per year, while five 24-hour cycles at the same temperature with cooling to room temperature each day give less than about 1.1 mm per year. In severe 3000-cycle testing its resistance is reported as better than that of ASTM TP310 and EN 1.4828 (TP309).
Carburising, sulphidising and nitrogen-bearing atmospheres
Carburisation resistance is good under oxidising conditions because of the chromium, silicon and rare-earth oxide. In strongly reducing or alternately oxidising and carburising atmospheres, higher-chromium or higher-nickel grades such as 310, 314 or Alloy 800H are more resistant. The grade resists sulphur-bearing gases provided at least traces of oxygen are present to maintain the oxide. In gas shields containing little or no oxygen it is inferior to Alloy 800H and 25Cr/20Ni steels, and it is not recommended for muffle tubes in cracked-ammonia atmospheres.
Structural stability and sensitisation
Because the chromium level is moderate and nitrogen is added, 1.4835 is much less prone to sigma-phase embrittlement than 25Cr/20Ni steels. It sensitises between about 425 °C and 860 °C, which is not an issue for high-temperature service but reduces aqueous corrosion resistance afterwards. Pitting resistance in the annealed condition approximates that of 316 because of the high chromium and nitrogen, although the grade is not intended for wet-corrosion duty.
5. Forging, heat treatment, welding and machining
| Operation | Temperature and practice |
|---|---|
| Hot working and open-die forging | about 900-1150 °C; finish forging above the lower limit, then solution anneal |
| Hot bending | 850-1100 °C, followed by solution annealing |
| Solution annealing, final condition | 1050-1150 °C, 5-20 min, rapid cooling in air or water. ASTM A473 requires 1040 °C minimum with cooling fast enough to avoid grain-boundary carbides |
| Stress relieving | 850-950 °C, 10-15 min, cooling in air |
| Cold work | Good formability, but higher forces than 1.4841 because of the nitrogen content; allow for springback. Solution anneal after 10-20 % cold work where maximum creep strength is required |
| Hardening | Not hardenable by heat treatment; solid-solution grade |
| Welding | Good weldability. TIG/GTAW preferred, also MMA/SMAW and MIG. Filler EN ISO 14343-A G 21 10 N (1.4829) or EN ISO 3581-A E Z 23 10 N R 12. Use 309-type fillers only where lower creep strength is acceptable. Heat input below 1.5 kJ/mm, interpass temperature below 150 °C |
| Machining | As with other austenitic stainless steels: sharp tools, slow speeds and heavy positive feed. The grade is low in sulphur, so chips are tough |
6. Specifications, equivalents and approvals
| System | Designation or standard |
|---|---|
| EN | 1.4835, X9CrNiSiNCe21-11-2 (EN 10095 heat resisting steels; also listed in EN 10088-1) |
| ASTM / UNS | UNS S30815: A182 F45 for forged flanges, fittings and valve parts; A473 for stainless forgings; A479 for bars and shapes in boilers and pressure vessels; A240 for plate and sheet; A213 and A312 for tube and pipe |
| ASME | Accepted in the ASME Boiler and Pressure Vessel Code Sections I, III and VIII Div. 1 as SA-182, SA-213, SA-240, SA-249, SA-312 and SA-479 |
| European pressure forgings | EN 10222-5, martensitic, austenitic and austenitic-ferritic stainless steel forgings for pressure purposes |
| Other and obsolete | Sweden SS 2368; related designations 1.4893 and X8CrNiSiN21-11; trade cross-references 253 MA (Outokumpu trademark) and RA 253 MA |
| NDT | EN 10228-4 for ultrasonic testing of austenitic and austenitic-ferritic stainless steel forgings; ASTM A388/A388M for heavy steel forgings |
| Certification | EN 10204 type 3.1, issued by the manufacturer's authorised inspection representative, or type 3.2, countersigned by an independent third party |
Equivalents are functional comparisons, not contractual substitutions. Where an exact grade is required the original specification governs. State the specification and edition on the enquiry and we will certify to it.
When another grade is the better choice
310 and 310S are preferred where the atmosphere is carburising and a higher nickel content is needed. 304H is a lower-cost option if the metal temperature stays below roughly 800 °C. A nickel-base alloy such as Incoloy 800H, Inconel 600 or Inconel 601 should be used above the 1100 to 1150 °C ceiling of 1.4835 or in strongly reducing atmospheres. We forge all of these grades and can quote alternatives side by side.
7. Typical applications of 1.4835 forged parts
Because 1.4835 combines creep strength with cyclic-oxidation resistance, the forged components most often ordered from us are furnace and flue-gas hardware and high-temperature valve and rotating parts.
- Furnace and heat-treatment hardware: burner components, retorts, radiant and muffle tubes, furnace rollers, walking beams, hoods, flues, grates, jigs and baskets, refractory anchors, expansion bellows, thermocouple protection tube flanges and forged supports.
- Metallurgical plant: lances and shafts for pulverised-coal injection in blast furnaces, recuperator and waste-heat-recovery components, muffle tube parts for continuous wire annealing furnaces.
- Combustion and waste treatment: fluidised-bed combustion plant parts, sludge incinerator components, thermal oxidiser internals, carbon-black process gas cooler and air heater tube sheets, forged flanges and nozzles.
- Petrochemical and chemical: styrene reactor and EDC cracking tube components, convection tube parts in ethylene cracking, air preheater and tube hanger parts in sulphuric acid gas converters, refinery service exposed to polythionic acid.
- Glass, cement, pulp and paper: moulds, ash hopper covers, pipe hooks, impact separators, forged rolls and wheels.
- Valves and rotating equipment: valve bodies, blocks, bonnets, stems and seat rings for ball, gate, globe, check and plug valves; turbine, gas-compressor and fan rotor forgings; spindles, gears and gearbox shafts.
8. Ordering 1.4835 forgings
Jiangyin Jiangnan Metal Co., Ltd. is an open-die forging factory at No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China, producing forged and ring-rolled parts in 1.4835 and in carbon, alloy, tool and stainless steels and nickel alloys. All 1.4835 forgings are supplied solution annealed, with mechanical testing on prolongations or sacrificial rings as required by the ordering specification, and with an EN 10204 3.1 or 3.2 inspection document.
| Item | Scope |
|---|---|
| Product forms | Rings, seamless rolled rings, flanges, discs, bars, shafts, sleeves, bushings, hollow bars, tube sheets, valve parts and custom open-die shapes |
| Delivery condition | Forged and solution annealed; rough machined, proof machined or finish machined |
| Size and weight | Confirmed against the drawing at enquiry stage, together with the forging ratio and test location |
| Testing | Chemical analysis, room and elevated temperature tensile, hardness, grain size, PMI, PT, ultrasonic examination to ASTM A388 or EN 10228-4 |
| Documentation | EN 10204 3.1 or 3.2 certificate, heat and part traceability, NDT reports, dimensional report |
| Quotation | Send a drawing or sketch with specification, quantity and certification level. Written quotation normally issued within 24 working hours |
9. Frequently asked questions about 1.4835
What is 1.4835 steel?
1.4835 (EN name X9CrNiSiNCe21-11-2, UNS S30815) is a heat-resistant austenitic chromium-nickel stainless steel containing about 20-22 % Cr, 10-12 % Ni and 1.4-2.5 % Si, with nitrogen and cerium additions. The silicon, nitrogen and rare-earth additions form a thin, adherent and elastic oxide that gives high creep strength and oxidation resistance in air to about 1150 °C.
Is 1.4835 the same as UNS S30815 and 253 MA?
Yes, the same grade family: 1.4835 equals X9CrNiSiNCe21-11-2, UNS S30815 and SS 2368 (obsolete). "253 MA" is a registered trademark of Outokumpu covering this composition, so it should be used only as a cross-reference. Note the small differences in limits: EN 10095 allows C up to 0.12 %, Si up to 2.50 % and S up to 0.015 %, while ASTM A182 F45 and A473 allow C up to 0.10 %, Si 1.40-2.00 % and S up to 0.030 %.
What is the maximum service temperature?
About 1150 °C in air. For load-bearing and pressure-containing parts the grade is typically used from roughly 500 °C up to about 900 °C, where its strength exceeds that of alternatives such as 310. Above 1100 to 1150 °C, or in strongly reducing or carburising gas, choose a nickel-base alloy.
Which standards apply to 1.4835 forged rings and flanges?
ASTM A182/A182M Grade F45 for high-temperature forged flanges, fittings and valve parts; ASTM A473 for general-purpose stainless forgings; ASTM A479 for bars and shapes in boilers and pressure vessels; ASTM A240 for plate; EN 10222-5 for European pressure forgings; EN 10095 for the grade itself. The grade is accepted in the ASME Boiler and Pressure Vessel Code as SA-182, SA-213, SA-240, SA-249, SA-312 and SA-479.
What are the guaranteed mechanical minimums for forgings?
ASTM A182 F45 and A473 (S30815): tensile 87 ksi (600 MPa) minimum; yield at 0.2 % offset 45 ksi (310 MPa) minimum; elongation 40 % minimum in 2 in. (50 mm) or 4D; reduction of area 50 % minimum. EN 10095 solution-annealed material is quoted as Rm 650-850 MPa, Rp0.2 310 MPa minimum, hardness about 190 HV.
How are 1.4835 forgings inspected?
Ultrasonic testing of austenitic stainless steel forgings is covered by EN 10228-4; EN 10228-3 applies to ferritic and martensitic forgings only. ASTM A388/A388M may be used instead. We also supply PT, PMI, grain size, hardness, room and elevated temperature tensile results, and an EN 10204 3.1 or 3.2 certificate.
Who supplies 1.4835 open-die forgings?
Jiangyin Jiangnan Metal Co., Ltd., No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province 214423, China, forges 1.4835 / UNS S30815 rings, rolled rings, flanges, bars, discs, sleeves, bushings, tube sheets, shafts and valve parts to customer drawings. Contact sales@steelforgepieces.com or +86-189-2135-9659.
10. Related grades we forge
Other heat-resistant and corrosion-resistant grades in our range: AISI 330, A182 F44, Nitronic 60, Sanicro 28, 904L, A286, Incoloy 800H, Incoloy 800HT, Alloy 45TM, Alloy 602, Haynes 230. See all stainless steel forgings and nickel alloy forgings.
Sources and disclaimer
Grade data on this page is consolidated from EN 10095 grade tables for 1.4835 / X9CrNiSiNCe21-11-2; ASTM A473 Tables 1 and 2 for UNS S30815; ASTM A182/A182M Grade F45 chemical and mechanical requirements; ASTM A388/A388M and EN 10228-4 for ultrasonic examination; EN 10204 for inspection document types; and published mill data sheets for grade 253 MA / UNS S30815 covering oxidation, carburisation, creep and physical property values. 253 MA is a trademark owned by Outokumpu and is quoted here for identification only. Values are typical figures or specification minima given for information and are not a warranty. Order-specific properties are confirmed on the EN 10204 certificate issued with each heat.
Page reference: Jiangyin Jiangnan Metal Co., Ltd., "1.4835 Forgings: X9CrNiSiNCe21-11-2 / UNS S30815 Heat-Resistant Stainless Steel", steelforgepieces.com, updated 26 September 2026. A plain-text version of this page is available at 1.4835.md.