# 1.4835 Forgings: X9CrNiSiNCe21-11-2 / UNS S30815 Heat-Resistant Stainless Steel

Source page: https://www.steelforgepieces.com/Stainless-Steel/1.4835.html
Supplier: Jiangyin Jiangnan Metal Co., Ltd., open-die forging factory, No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province 214423, China. Tel +86-189-2135-9659. Email sales@steelforgepieces.com
Updated: 26 September 2026

## 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. For forgings the grade is ordered as ASTM A182 Grade F45 (flanges, fittings, 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.

Product forms forged by Jiangyin Jiangnan Metal in this grade: 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.

## 1. Chemical composition, % by mass

Single values are maxima unless a range is shown.

| Element | EN 10095 (1.4835) | ASTM A182 F45 / A473 (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 | Balance | 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, solution-annealed condition

| 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. |

Minimum elevated-temperature strength:

| 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-rupture strength, MPa, mean values. Above about 550 C, design is governed by creep rupture rather than by Rp0.2.

| 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 | 200 GPa at 20 C; 185 GPa at 200 C; 155 GPa at 600 C; 120 GPa at 1000 C |
| Mean thermal expansion | 17.0e-6 /C (0-100 C); 18.5e-6 (0-600 C); 19.5e-6 (0-1000 C) |
| Thermal conductivity | about 13-15 W/m.K at 20 C, about 29 W/m.K at 1000 C |
| Specific heat (0-100 C) | about 490-500 J/kg.K |
| Electrical resistivity at 20 C | about 0.84-0.85 microohm.m |
| Relative magnetic permeability | about 1.003, practically non-magnetic when annealed |

## 4. High-temperature behaviour

Oxidation in air: the grade forms a thin, highly adherent and elastic chromium-oxide scale and performs well under cyclic as well as isothermal heating. 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; five 24-hour cycles at the same temperature with daily cooling to room temperature give less than about 1.1 mm per year. In severe 3000-cycle testing the resistance is reported as better than ASTM TP310 and EN 1.4828 (TP309).

Carburising and sulphidising: carburisation resistance is good under oxidising conditions. In strongly reducing or alternately oxidising and carburising atmospheres, 310, 314 or Alloy 800H are more resistant. Sulphur-bearing gases are tolerated provided at least traces of oxygen maintain the oxide. In gas shields with little or no oxygen the grade is inferior to Alloy 800H and 25Cr/20Ni steels, and it is not recommended for muffle tubes in cracked-ammonia atmospheres.

Structural stability: less prone to sigma-phase embrittlement than 25Cr/20Ni steels because of the moderate chromium level and the nitrogen addition. Sensitisation occurs between about 425 C and 860 C, which does not affect high-temperature use but reduces aqueous corrosion resistance afterwards. Pitting resistance in the annealed condition approximates that of 316, 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, 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, higher forces than 1.4841 because of the nitrogen; solution anneal after 10-20 % cold work where maximum creep strength is required |
| Hardening | Not hardenable by heat treatment; solid-solution grade |
| Welding | 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. Heat input below 1.5 kJ/mm, interpass below 150 C |
| Machining | Sharp tools, slow speeds, heavy positive feed; low sulphur content makes chips tough |

## 6. Specifications, equivalents and approvals

| System | Designation or standard |
|---|---|
| EN | 1.4835, X9CrNiSiNCe21-11-2 (EN 10095; also listed in EN 10088-1) |
| ASTM / UNS | UNS S30815: A182 F45 (forged flanges, fittings, valve parts), A473 (stainless forgings), A479 (bars and shapes), A240 (plate and sheet), A213 and A312 (tube and pipe) |
| ASME | Accepted in ASME BPVC Sections I, III and VIII Div. 1 as SA-182, SA-213, SA-240, SA-249, SA-312, SA-479 |
| European pressure forgings | EN 10222-5 |
| Other and obsolete | Sweden SS 2368; related 1.4893 and X8CrNiSiN21-11; trade cross-references 253 MA (Outokumpu trademark), RA 253 MA |
| NDT | EN 10228-4 (austenitic and austenitic-ferritic stainless steel forgings), ASTM A388/A388M (heavy steel forgings) |
| Certification | EN 10204 type 3.1 (manufacturer's authorised inspection representative) or type 3.2 (countersigned by an independent third party) |

Equivalents are functional comparisons, not contractual substitutions. EN 10228-3 covers ferritic and martensitic forgings and should not be applied to this austenitic grade.

Alternatives: 310 and 310S where the atmosphere is carburising and higher nickel is needed; 304H where metal temperature stays below roughly 800 C; Incoloy 800H, Inconel 600 or Inconel 601 above the 1100 to 1150 C ceiling of 1.4835 or in strongly reducing atmospheres.

## 7. Typical applications of 1.4835 forged 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, 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 and inspection

All 1.4835 forgings are supplied solution annealed, with mechanical testing on prolongations or sacrificial rings as required by the ordering specification.

| Item | Scope |
|---|---|
| Melting route | EAF + VOD, ESR available |
| Delivery condition | Forged and solution annealed; rough, proof or finish machined |
| Size and weight | Confirmed against the drawing at enquiry stage, with 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 | Drawing or sketch with specification, quantity and certification level; written quotation normally within 24 working hours |

## 9. FAQ

**What is 1.4835 steel?** A heat-resistant austenitic chromium-nickel stainless steel, EN 1.4835 / X9CrNiSiNCe21-11-2 / UNS S30815, with about 20-22 % Cr, 10-12 % Ni, 1.4-2.5 % Si and additions of nitrogen and cerium. The oxide formed is thin, adherent and elastic, giving high creep strength and oxidation resistance in air to about 1150 C.

**Is 1.4835 the same as UNS S30815 and 253 MA?** Same grade family. 253 MA is an Outokumpu trademark, so it is used only as a cross-reference. EN 10095 allows C up to 0.12 %, Si up to 2.50 % and S up to 0.015 %; ASTM A182 F45 and A473 allow C up to 0.10 %, Si 1.40-2.00 % and S up to 0.030 %.

**Maximum service temperature?** About 1150 C in air. Load-bearing and pressure-containing parts are typically used from roughly 500 C up to about 900 C. Above 1100 to 1150 C, or in strongly reducing or carburising gas, use a nickel-base alloy.

**Which standards apply to forged rings and flanges?** ASTM A182 F45, ASTM A473, ASTM A479, ASTM A240, EN 10222-5, with the grade defined in EN 10095. Accepted in ASME BPVC as SA-182, SA-213, SA-240, SA-249, SA-312 and SA-479.

**Guaranteed mechanical minimums for forgings?** 87 ksi (600 MPa) tensile, 45 ksi (310 MPa) yield at 0.2 % offset, 40 % elongation, 50 % reduction of area, per ASTM A182 F45 and A473.

**How should forgings be heat treated?** Hot work between about 900 and 1150 C, then solution anneal at 1050-1150 C for 5 to 20 minutes with rapid cooling in air or water. ASTM A473 requires 1040 C minimum with cooling fast enough to prevent grain-boundary carbides. Stress relieve at 850-950 C for 10 to 15 minutes, air cooled. The grade is not hardenable by heat treatment and sensitises between about 425 C and 860 C.

**How are forgings inspected?** Ultrasonic testing to EN 10228-4 or ASTM A388/A388M, plus PT, PMI, grain size, hardness and tensile testing, with 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. Tel +86-189-2135-9659, email sales@steelforgepieces.com.

## 10. Related grades

AISI 330, A182 F44, Nitronic 60, Sanicro 28, 904L, A286, Incoloy 800H, Incoloy 800HT, Alloy 45TM, Alloy 602, Haynes 230.

Category index: https://www.steelforgepieces.com/Stainless-Steel/ and https://www.steelforgepieces.com/Nickel-Alloy/

## Sources and disclaimer

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; ASTM A388/A388M and EN 10228-4; EN 10204; and published mill data sheets for grade 253 MA / UNS S30815 covering oxidation, carburisation, creep and physical properties. 253 MA is a trademark owned by Outokumpu, quoted 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.