Heat-resistant austenitic stainless steel
353 MA Forgings UNS S35315 · EN 1.4854 · X6NiCrSiNCe35-25 · 25Cr-35Ni-Ce
353 MA is an austenitic heat-resistant stainless steel of about 25 % chromium and 35 % nickel, micro-alloyed with nitrogen and cerium. Metalcor rates it resistant to scaling in air up to 1100 C with good creep rupture strength. Alleima attributes its performance in oxidizing, carburizing and nitriding atmospheres to the nitrogen and rare earth metal additions. The grade belongs in furnace and high-temperature process hardware, not in seawater or acid service.
Jiangyin Jiangnan Metal melts its own steel and forges 353 MA into seamless rolled rings, flanges, shafts, discs, bars and tube sheets to drawing. Rings roll to 6,000 mm outside diameter and single pieces run to 30 tonnes.
- Type
- Austenitic heat-resistant stainless steel
- Nominal
- 25 Cr · 35 Ni · Ce + N
- UNS
- S35315
- EN
- 1.4854 · X6NiCrSiNCe35-25
- Scaling
- Resistant in air to 1100 C
- Rm
- 650 to 800 N/mm²
- Rp0.2
- 300 N/mm² minimum
- Forms
- Rolled rings, rings, flanges, shafts, discs, bars, tube sheets, sleeves
- Max piece
- 30 t · ring OD to 6,000 mm
- MOQ
- 10 kg, no minimum piece count
- Lead time
- 20 to 60 days
Designations and equivalents
353 MA began as a mill brand, Avesta 353 MA, and is now supplied under the Alleima name. Rolled Alloys markets the same chemistry as RA 353 MA. Order against UNS S35315 or EN 1.4854 rather than the trade name, so the chemistry is fixed by a public specification instead of one producer's literature.
| Common names | 353 MA, 353MA, Alloy 353 MA, Avesta 353 MA, Alleima 353 MA, RA 353 MA |
|---|---|
| UNS | S35315 |
| EN material number | 1.4854 |
| EN designation | X6NiCrSiNCe35-25 |
| Alloy class | Austenitic heat-resistant stainless steel, 25Cr-35Ni, nitrogen and cerium micro-alloyed. Also classed as super-austenitic on account of the total alloy content. |
| Product standards | ASTM A240 (plate, sheet, strip), ASTM A479 (bars and shapes for boilers and other pressure vessels), ASTM A959 (harmonised wrought stainless compositions), EN 10095 (heat resisting steels and nickel alloys) |
| Welding consumable | Matching 1.4854 filler. Metalcor notes preheat and post-weld heat treatment are normally not required. |
There is no dedicated ASTM forging specification for S35315 in the way ASTM A182 covers F51 or F316L. Forgings in this grade are ordered against a customer or project specification that calls up the S35315 or 1.4854 chemistry, the delivery condition, the mechanical test requirements and the NDT acceptance class. Send us the specification you intend to invoke and we will confirm in writing what can be certified against it before the order is placed.
Chemical composition
Two columns below, because they answer different questions. The EN 1.4854 column is what a certificate has to satisfy. The harmonised range is the wider band permitted for UNS S35315 in the ASTM system, which matters if you are dual-certifying a part.
| Element | EN 1.4854 limit | S35315 harmonised range | Typical analysis |
|---|---|---|---|
| C — Carbon | 0.07 max | 0.040 to 0.080 | 0.050 |
| Si — Silicon | 1.30 max | 1.2 to 2.0 | 1.3 |
| Mn — Manganese | 1.50 max | 2.0 max | — |
| P — Phosphorus | 0.040 max | 0.040 max | — |
| S — Sulphur | 0.015 max | 0.030 max | — |
| Cr — Chromium | 24.0 to 26.0 | 24.0 to 26.0 | 25 |
| Ni — Nickel | 34.0 to 36.0 | 34.0 to 36.0 | 35 |
| N — Nitrogen | 0.17 max | 0.12 to 0.18 | 0.17 |
| Ce — Cerium | 0.03 to 0.08 | 0.03 to 0.08 | 0.05 |
| Fe — Iron | Balance | Balance | about 37 |
An earlier version of this page gave carbon as 0.7 %. That was a decimal point error and it has been corrected: Metalcor specifies 0.07 % maximum for EN 1.4854 and MakeItFrom gives 0.040 to 0.080 % for UNS S35315. If you hold an older printout from this site, use this revision instead.
Separately, the AZoM datasheet for grade 353MA lists cerium at 1.3 %, the same figure it gives for silicon. That conflicts with the 0.03 to 0.08 % cerium range specified by Metalcor for 1.4854 and appears to be a transcription error in that table. Use 0.03 to 0.08 % when writing a purchase specification.
Mechanical properties
Room temperature, solution annealed. Design to the specified minima, not to the typical column. Where the published sources disagree the range is shown rather than averaged, because averaging two datasheets produces a number that neither of them supports.
| Property | Specified | Reported typical |
|---|---|---|
| Tensile strength, Rm | 650 to 800 N/mm² | 720 to 740 MPa, 104 to 110 ksi |
| Proof strength, Rp0.2 | 300 N/mm² minimum | 360 MPa, 52 ksi |
| Elongation, A5 | 40 % minimum | 46 to 50 % |
| Hardness | 152 HB 30 maximum | 190 HB, 82 HRB |
| Modulus of elasticity | 190 kN/mm² | 190 to 200 GPa |
| Shear modulus | — | 78 GPa |
| Shear strength | — | 520 MPa, 75 ksi |
| Fatigue strength | — | 280 MPa, 41 ksi |
| Poisson's ratio | — | 0.28 |
The hardness figures are the widest disagreement in the published data. Metalcor gives 152 HB 30 as a maximum for 1.4854, while MakeItFrom reports about 190 HB for annealed S35315. If your drawing carries a hardness acceptance limit, state the test method and the limit on the enquiry so the heat treatment is set to meet it rather than assumed.
Physical and thermal properties
| Property | Metric | Imperial |
|---|---|---|
| Density | 7.9 g/cm³ | 0.285 lb/in³ |
| Specific heat capacity | 480 J/kg·K | 0.12 BTU/lb·F |
| Thermal conductivity | 11 to 12 W/m·K | 6.8 BTU/h·ft·F |
| Electrical resistivity | 1 Ω·mm²/m | — |
| Latent heat of fusion | 330 J/g | — |
| Melting onset, solidus | 1330 C | 2420 F |
| Melting completion, liquidus | 1370 C | 2510 F |
| Scaling resistance in air | 1100 C | 2010 F |
| Maximum mechanical temperature | 1100 C | 2010 F |
| Maximum corrosion temperature | 450 C | 840 F |
Metalcor states 1.4854 is resistant to scaling in air up to 1100 C, and MakeItFrom gives 1100 C as the maximum mechanical temperature for S35315. AZoM cites 1150 C as the maximum service temperature in air. The figures describe different limits: scale growth, load-bearing capability and bare survival in an unloaded part are not the same test.
AZoM adds a point that matters more than the ceiling. Service below 950 C may cause reduced room temperature impact toughness. A part cycled through the intermediate range can therefore end up less tough at ambient than it was as delivered, which is a maintenance and inspection issue rather than a purchase issue. Take the allowable temperature from your design code and the real atmosphere, not from a supplier datasheet.
What the grade is good at
Oxidation resistance
Cerium at 0.03 to 0.08 % with silicon around 1.3 % builds a dense, adherent chromium oxide scale. ASM Alloy Digest describes RA 353 MA as a 25Cr-35Ni alloy designed for oxidation resistance above 1800 F.
Carburising and nitriding atmospheres
Alleima states that the nitrogen and rare earth metal additions give high performance in oxidizing, carburizing and nitriding environments. The high nickel content is what limits carbon pick-up.
Creep rupture strength
Metalcor rates 1.4854 as having good creep rupture strength. For load-bearing furnace hardware this, not room temperature tensile, is the property that sets service life.
Weldability without PWHT
Metalcor lists matching 1.4854 filler and notes that preheating and post-weld heat treatment are normally not necessary, which simplifies field repair of fabricated assemblies.
Where 353 MA forgings are used
Metalcor lists heat treatment furnaces as the application for 1.4854. In forged rather than tubular form that translates into the static and rotating hardware around the furnace, where metal temperature rather than chemical attack sets the life of the part.
Furnace and heat treatment hardware
Retort and muffle flanges, radiant tube flanges and support rings, burner block rings, roller hearth shafts, bushings and sleeves, fan hubs, hearth components and machined rings for furnace internals.
High temperature process plant
Flanges, header rings and tube sheets for cracking, reforming and waste heat recovery duty, transfer line components, and forged fittings adjacent to furnace coils where carburisation resistance decides the material choice.
Cement, lime and mineral processing
Kiln nose ring and burner pipe components, cooler and grate parts, cyclone and riser duct rings, and seats exposed to hot dust-laden gas.
Incineration and energy recovery
Recuperator tube sheets, boiler penetration flanges, forged discs and rings for hot gas expanders, and sleeves for high temperature ducting.
This is not a seawater, chloride or acid alloy. MakeItFrom gives a maximum corrosion temperature of 450 C for S35315, against a 1100 C mechanical limit, and the grade carries no molybdenum. It should not be substituted into subsea, firewater, desalination, reverse osmosis or sulphuric acid duty.
For those services specify A182 F51, F53 or F55 duplex forgings, the 6Mo austenitic A182 F44, 904L, or a nickel alloy such as Hastelloy C-276 or Inconel 625. If the grade on your enquiry does not match the service you describe, we will say so before quoting. A wrong grade shipped correctly is still a failed order.
Forged product forms
Open-die forged or ring-rolled from steel melted on site, then heat treated, machined and tested in the same works. No welding, no casting, no purchased billet of unknown origin.
Seamless rolled rings
Radial-axial rolled from a punched preform, rectangular or contoured section, outside diameter from 50 mm to 6,000 mm.
Forged rings
Upset and punched for sections outside the ring mill envelope, and where heavy reduction is preferred to rolling.
Flanges
Weld neck, blind, slip-on, lap joint and special profile, to drawing or to the dimensional standard your project invokes.
Shafts and spindles
Stepped, eccentric and roller hearth shafts. Long shafts quench vertically in the 15 m well furnaces, turned to 14 m.
Discs and tube sheets
Solid and bored discs, covers and tube sheets, supplied proof-machined where volumetric inspection is required.
Sleeves, bushings, hollow bar
Trepanned or bored from solid forged blanks, to 1,600 mm diameter by 10,000 mm on the deep-hole drilling machine.
Bar and blocks
Round, square and flat forged bar in cut lengths, the feedstock route for machined-from-solid components.
Nozzles and bodies
Forged nozzles, blocks, bodies and heavy-wall pipe sections for high temperature service assemblies.
Melting, forging and heat treatment
The properties of this grade depend on a fully austenitic structure with the cerium and nitrogen held in solution, so the route matters as much as the ladle analysis.
Melting
Carbon, alloy, stainless and duplex grades run through the 25 t electric arc furnace, are refined in the 25 t and 50 t ladle furnaces and decarburised in the 30 t or 60 t vacuum oxygen decarburisation units, which is the normal route for 353 MA. Vacuum oxygen decarburisation is what allows carbon to be pulled to the 0.07 % maximum while nitrogen is held at the 0.12 to 0.18 % the grade needs. Where a project calls for a remelted product, protective-atmosphere electroslag remelting at 3 t and 6 t is available on site. Maximum heat size is 60 tonnes.
Forging
353 MA is a stiff, high-nickel austenitic steel with a narrower hot working window than a carbon or low-alloy grade, so it is worked with controlled reheats rather than pushed for reduction in a single heat. Presses are 6,300 t, 4,000 t and 2,000 t, with three radial-axial ring mills at 6 m, 3 m and 1 m and hammers from 750 kg to 5 t. The forging plan is set to achieve the reduction needed for grain refinement through the section, not only at the surface.
Heat treatment
Forgings are solution annealed and cooled quickly, to dissolve carbides and keep the cerium and nitrogen in solution. Slow cooling through the intermediate range is avoided, since precipitation in that band is the mechanism behind the loss of room temperature toughness. Three high-temperature car-bottom furnaces cover the solution treatment range, and two 15 m well-type furnaces allow long shafts to be quenched vertically without distortion. The treatment condition and cooling medium are recorded on the certificate.
Testing and certification
Because the steel is melted here, chemistry is verified at the furnace rather than taken from a supplier's certificate. The test scope is agreed before production and written into the order acknowledgement.
| Discipline | Method | Standard |
|---|---|---|
| Chemical analysis | Optical emission spectrometry, infrared carbon and sulphur | ASTM E415, ASTM E1019 |
| Alloy verification | Handheld PMI on the finished part | Positive material identification |
| Tensile | 600 kN and 300 kN universal testing machines | ASTM A370, ISO 6892 |
| Impact | Charpy V-notch with low temperature bath | ASTM A370 |
| Hardness | Portable Leeb, bench machine through accredited laboratory on request | ASTM A956, converted per ASTM E140 |
| Ultrasonic | Full-digital flaw detection, acceptance class stated on the certificate | ASTM A388, EN 10228-3, SEP 1921 |
| Magnetic particle and visual | Surface examination, endoscope for bores | ASTM E709 |
| Grain size | Metallography | ASTM E112 |
| Certification | Mill test certificate, or witnessed by BV, DNV, LR, SGS, TUV or your own inspector | EN 10204 3.1 or 3.2 |
| Approvals held | CCS, BV, DNV, LR, NK | Classification societies |
Intergranular corrosion testing to ASTM A262 or G28 and other order-specific tests outside the in-house scope are placed with an accredited third-party laboratory and the report issued alongside the mill certificate. State the requirement at enquiry stage so it is scheduled before shipment rather than added to the delivery date.
Frequently asked questions
What is 353 MA stainless steel?
An austenitic heat-resistant stainless steel of roughly 25 % chromium and 35 % nickel, micro-alloyed with nitrogen and cerium. It carries the designations UNS S35315 and EN 1.4854, EN name X6NiCrSiNCe35-25, and originated as the Avesta 353 MA brand, now supplied by Alleima. Rolled Alloys markets the same chemistry as RA 353 MA.
Metalcor describes 1.4854 as an austenitic heat-resistant steel with good creep rupture strength, resistant to scaling up to 1100 C. Alleima attributes its performance in oxidizing, carburizing and nitriding environments to the nitrogen and rare earth metal additions.
What is the carbon content of 353 MA?
Low. Metalcor specifies 0.07 % maximum for EN 1.4854. AZoM gives 0.050 % as a typical analysis, and MakeItFrom lists 0.040 to 0.080 % as the permitted range for UNS S35315.
Any figure near 0.7 % is a decimal point error. That error appeared on an earlier version of this page and has been corrected.
What is the maximum service temperature?
Metalcor rates 1.4854 resistant to scaling in air up to 1100 C. MakeItFrom gives 1100 C as the maximum mechanical temperature for S35315. AZoM cites 1150 C as the maximum service temperature in air. ASM Alloy Digest describes RA 353 MA as aimed at applications above 1800 F.
AZoM also warns that service below 950 C may cause reduced room temperature impact toughness. Take the allowable temperature from your design code and the actual atmosphere.
Is 353 MA suitable for seawater, chloride or acid service?
No. MakeItFrom gives a maximum corrosion temperature of 450 C for S35315, and the grade contains no molybdenum. It is an oxidation and carburisation grade for furnace and hot gas duty.
For wet corrosion service specify duplex or super duplex forgings such as A182 F51, F53 or F55, a 6Mo austenitic such as A182 F44 or 904L, or a nickel alloy such as Hastelloy C-276 or Inconel 625.
Why is cerium added, and does it survive forging?
Cerium is a rare earth metal specified at 0.03 to 0.08 % by Metalcor. With the elevated silicon it improves the density and adherence of the protective chromium oxide scale, which is what allows sustained service near the 1100 C limit and resists carbon and nitrogen pick-up.
It survives forging provided the heat treatment keeps it in solution, which is why the solution annealing temperature and the cooling medium are recorded on the certificate rather than left to the shop.
Which standards cover 353 MA product forms?
MakeItFrom lists ASTM A240 for plate, sheet and strip and ASTM A479 for bars and shapes for use in boilers and other pressure vessels. The grade also appears in ASTM A959, the harmonised composition system for wrought stainless steels, and in EN 10095 for heat resisting steels and nickel alloys.
There is no dedicated ASTM forging specification for S35315. Forgings are ordered against a customer or project specification calling up the chemistry, the delivery condition, the mechanical tests and the NDT acceptance class.
How does 353 MA compare with AISI 330 or Incoloy 800H?
All three are high nickel austenitic grades used well above 800 C, and the right one depends on which mechanism governs your part: oxidation, carburisation, creep rupture or thermal cycling, plus whether the grade is accepted by the code the equipment is built to.
ASM Alloy Digest positions RA 353 MA as a 25Cr-35Ni alloy aimed at oxidation resistance above 1800 F. Rather than publish a general ranking that would be wrong for half of the cases, send the metal temperature, the atmosphere and the stress and the published creep and oxidation data for each candidate will be compared before you commit.
What size and weight can you forge, and what is the minimum order?
Seamless rings roll to 6,000 mm outside diameter on the 6 m radial-axial mill, with 3 m and 1 m mills below that and an upset-and-punch route from 50 mm outside diameter. The heaviest single piece is 30 tonnes. Shafts turn to 14 m and bores run to 1,600 mm diameter by 10,000 mm.
Minimum order is 10 kg with no minimum piece count, so a single prototype ring is quotable. Normal lead time is 20 to 60 days, at the longer end when a remelting step or third-party witnessed inspection is required.
Who manufactures these forgings?
Jiangyin Jiangnan Metal Co., Ltd., an integrated melting works and open-die forge at No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China, operating since 1997 with 460 staff and CCS, BV, DNV, LR and NK approvals.
Enquiries to sales@steelforgepieces.com or +86 189 2135 9659. Customer audits and third-party inspections are welcome.
Request a 353 MA quotation
Send the grade, the dimensions or a drawing, the quantity, the delivery condition, the test and certification requirements and the destination port. Include the metal temperature and the atmosphere and we will confirm the grade suits the duty before pricing it. Quotations normally go back within two working days.
- Company
- Jiangyin Jiangnan Metal Co., Ltd.
Open-die forging factory, established 1997 - Works
- No.1 Chengxiqiao Road, Zhouzhuang Town,
Jiangyin City, Jiangsu Province, China - Telephone and WhatsApp
- +86 189 2135 9659
- sales@steelforgepieces.com
- Website
- www.steelforgepieces.com
- Minimum order
- 10 kg, no minimum piece count
- Lead time
- 20 to 60 days
- Certification
- EN 10204 3.1 as standard, 3.2 witnessed on request. CCS, BV, DNV, LR, NK approved works.