Heat-resistant austenitic stainless steel
UNS S30815 Forgings ASTM A182 Grade F45 · EN 1.4835 X9CrNiSiNCe21-11-2 · SS 2368
GRADE DATA SHEET · JIANGYIN JIANGNAN METAL CO., LTD. · UPDATED
UNS S30815 is a heat-resistant austenitic stainless steel with 20.0 to 22.0 % chromium, 10.0 to 12.0 % nickel, raised silicon, 0.14 to 0.20 % nitrogen and 0.03 to 0.08 % cerium. The silicon, nitrogen and cerium additions give oxide stability, high strength at elevated temperature and resistance to sigma phase precipitation. It resists oxidation in air up to 1150 °C and gives superior service to Grade 310 in carbon, nitrogen and sulphur bearing atmospheres. In forged form the grade is ordered as ASTM A182 Grade F45.
- Oxidation in air
- 1150 °C
- Tensile, min
- 600 MPa
- Yield 0.2 %, min
- 310 MPa
- Elongation, min
- 40 %
- Hardness, max
- 217 HB
- Forging grade
- A182 F45
Designations
| System | Designation | Notes |
|---|---|---|
| UNS | S30815 | Flat rolled product in ASTM A240 / A240M, bar in A276, forgings in A182 |
| ASTM / ASME forgings | F45, SA-182 F45 | Listed as 21 chromium, 11 nickel modified with nitrogen and cerium |
| Euronorm number | 1.4835 | Name X9CrNiSiNCe21-11-2 |
| Swedish SS | 2368 | — |
| Old British BS / En | — | No equivalent listed |
| Japanese JIS | — | No equivalent listed |
| Proprietary names | 253MA, 2111HTR | 253MA originated with Outokumpu, formerly Avesta. Shown for cross-reference only |
On equivalence. Published comparison tables for this grade are approximate. They list functionally similar materials, not contractual equivalents. Where an exact equivalent is required, the original specification must be consulted. We supply against the standardised designations S30815, A182 F45 and EN 1.4835.
Chemical Composition
Two composition windows apply, depending on which specification the order is placed against. ASTM A182 Grade F45, the forging grade, holds silicon to 1.40 to 2.00 %. ASTM A240 for flat rolled product allows 1.10 to 2.00 %. Where a drawing calls up A182 F45, the narrower silicon range governs and should be stated on the enquiry.
| Element | A182 F45 forgings | A240 S30815 plate | Role |
|---|---|---|---|
| Carbon | 0.05 – 0.10 | 0.05 – 0.10 | Strength at temperature. Also the reason the grade sensitises |
| Chromium | 20.00 – 22.00 | 20.0 – 22.0 | Protective oxide |
| Nickel | 10.00 – 12.00 | 10.0 – 12.0 | Austenite stability, kept deliberately low |
| Silicon | 1.40 – 2.00 | 1.10 – 2.00 | Oxide stability |
| Nitrogen | 0.14 – 0.20 | 0.14 – 0.20 | Strength at elevated temperature |
| Cerium | 0.03 – 0.08 | 0.03 – 0.08 | Oxide adherence under cyclic heating |
| Manganese | 0.80 max | 0.80 max | — |
| Phosphorus | 0.040 max | 0.040 max | Residual |
| Sulphur | 0.030 max | 0.030 max | Residual. Low sulphur limits machinability |
| Iron | Balance | Balance | — |
Cerium recovery depends on refining practice, which is one reason we melt this grade in house rather than buying billet. Chemistry is reported on the certificate against the melt number.
Mechanical Properties
| Property | A182 F45 forgings | A240 S30815 plate |
|---|---|---|
| Tensile strength, min | 600 MPa (87 ksi) | 600 MPa |
| Yield strength 0.2 % proof, min | 310 MPa (45 ksi) | 310 MPa |
| Elongation in 50 mm or 4D, min | 40 % | 40 % |
| Reduction of area, min | 50 % | Not specified |
| Hardness, max | Not specified | 217 HB / 95 HRB |
Strength at elevated temperature is higher than that of Grade 310, which is why the grade is chosen for structural and pressure-containing parts working above about 500 °C and up to about 900 °C. The austenitic structure also keeps toughness down to cryogenic temperature.
Physical Properties
| Property | Value |
|---|---|
| Density | 7800 kg/m³ |
| Elastic modulus | 200 GPa |
| Mean thermal expansion, 0 – 100 °C | 17.0 mm/m/°C |
| Mean thermal expansion, 0 – 600 °C | 18.5 mm/m/°C |
| Mean thermal expansion, 0 – 1000 °C | 19.5 mm/m/°C |
| Thermal conductivity at 20 °C | 15.0 W/m·K |
| Thermal conductivity at 1000 °C | 29.0 W/m·K |
| Specific heat, 0 – 100 °C | 500 J/kg·K |
| Electrical resistivity | 850 nΩ·m |
Published physical values differ slightly between mill data sheets. Treat the figures above as typical rather than guaranteed, and work to the values in the specification named on your order.
Heat and Corrosion Behaviour
Oxidation
Good resistance in air up to 1150 °C. At high temperature the steel quickly forms a thin, adherent and elastic oxide that keeps protecting the surface even under cyclic heating and cooling.
Carburisation
The grade performs well under oxidising conditions. If the atmosphere is reducing, alloys with higher nickel content are preferred. This is a real limit of a grade carrying only 10 to 12 % nickel and should be checked against your furnace atmosphere before ordering.
Sulphidation
Good resistance to sulphur bearing gases in an oxidising atmosphere, even where only traces of oxygen are present. The comparatively low nickel content is an advantage here against Grade 310 and high nickel alloys. Reducing gases prevent the protective oxide from forming.
Aqueous corrosion
This grade is not designed for aqueous corrosion resistance. The high chromium and nitrogen give pitting resistance approximating that of Grade 316, no better. The carbon content is high, so the grade is highly susceptible to sensitisation from welding or from service exposure, and it sensitises in the 425 to 860 °C range.
Sensitisation is not a problem for high temperature work, but it reduces aqueous corrosion resistance afterwards, which matters for any part that sees wet service after hot service. For chloride, seawater or stress corrosion duty, specify A182 F51, A182 F53 or A182 F44 instead.
Where another grade suits better
| Grade | Reason it might be chosen instead |
|---|---|
| Grade 310, AISI 330 | Carburising atmospheres that require higher nickel content |
| 304H | Lower cost, provided operating temperature stays below about 800 °C |
| Nickel alloys, for example Incoloy 800H or Inconel 601 | Carburising atmospheres, or service above the 1100 to 1150 °C ceiling of this grade |
Heat Treatment and Fabrication
Solution treatment. Heat to 1050 to 1150 °C and cool rapidly. The grade cannot be hardened by thermal treatment. Where material has been cold worked 10 to 20 %, solution treatment afterwards is recommended to reach maximum creep strength in service.
Welding. Good weldability by all standard fusion methods using matching filler metals. AS 1554.6 pre-qualifies welding of this grade with 22.12HT rods or electrodes. Grade 309 fillers can be used where lower creep strength is acceptable. Pure argon shielding gas should be used.
Machining. As with other austenitic stainless steels, use sharp tools, slow speeds and heavy feed. Sulphur content is low, so the grade is not free machining and tooling allowance should be planned accordingly.
Solution treatment is carried out in our own furnaces. Fourteen are available, the largest car-bottom chamber measuring 8,000 by 2,000 by 2,000 mm, with two well-type furnaces 15,000 mm deep by 1,500 mm diameter for vertical quenching of long parts.
Typical Applications
Furnace Components
Burners, retorts, conveyor belts, fans, jigs and baskets, rollers, walking beams, radiant tubes, electric heater elements, refractory anchors, hoods, flues, grates and expansion bellows.
Petrochemical and Refining
Tube hangers and tube supports in petrochemical plant and refineries, together with forged flanges and bodies for hot gas duty.
Heat Treatment Plant
Baskets, jigs and fixtures that cycle in and out of furnace temperature, where oxide spalling would otherwise shorten service life.
Structural at Temperature
Structural and pressure-containing parts working above about 500 °C and up to about 900 °C, where 304H has lost strength.
Final grade selection rests with the design authority. Send us the service temperature, the atmosphere and the loading, and our engineers will comment before you commit.
Supply Range
We melt and forge in one works at Jiangyin, Jiangsu, operating since 1997 with 460 staff including 9 senior engineers, 32 intermediate engineers and 140 technicians. Steel is melted on site rather than bought in as billet, so the certificate traces a part back to its melt number. Maximum heat size is 60 t, the largest press is 6,300 t, the ring mill rolls to 6,000 mm outside diameter and the heaviest single forging is 30 t.
| Form | Detail |
|---|---|
| Seamless rolled rings | Ring rolled from a punched preform on radial-axial mills, 1 m, 3 m and 6 m. Rectangular or contoured section, OD 50 to 6,000 mm |
| Forged rings | Upset and punched rings for sections outside the ring-mill envelope, and where heavy reduction is preferred to rolling |
| Forged flanges | Weld neck, blind, slip-on, socket weld, lap joint and orifice flanges to ASME B16.5 and B16.47, or to drawing, under A182 F45 |
| Shafts and spindles | Stepped shafts, gear shafts, eccentric shafts and spindles, turned to 14,000 mm length |
| Discs, tube sheets and covers | Solid and trepanned discs to 5,000 mm machined diameter, supplied proof machined for volumetric inspection |
| Forged bars and blocks | Round, flat and square bar cut to ordered length, peeled or rough turned on request |
| Cylinders, sleeves and bushings | Hollow forged sections bored from solid blanks, to 1,600 mm diameter by 10,000 mm |
| Valve components | Bodies, bonnets, seat rings, stems and blocks for ball, gate, globe, check and plug valves |
Ordering, Testing and Certification
Minimum order is 10 kg with no minimum piece count, so single prototype forgings are accepted alongside production batches. Lead time runs 20 to 60 days depending on material availability, forging ratio, heat treatment and the extent of testing called up.
Ultrasonic examination to EN 10228-3, SEP 1921 or ASTM A388 as called up on the order. Material certificates to EN 10204 3.1, or 3.2 with third party witness. Works approvals held include CCS, BV, DNV, LR and NK. Mechanical testing, grain size to ASTM E112 and positive material identification can be added as supplementary requirements.
Questions We Are Asked
What is UNS S30815 used for?
Parts that have to survive continuous or cyclic high temperature in air and in sulphur bearing oxidising atmospheres. Furnace burners, retorts, radiant tubes, rollers and walking beams, heat treatment baskets and jigs, refinery and petrochemical tube hangers, and forged flanges and valve parts on hot gas lines. It is specified where 304H has gone soft above 800 °C but a nickel alloy is not justified on cost.
Which ASTM grade covers S30815 forgings and flanges?
ASTM A182, Grade F45, which the standard describes as 21 chromium, 11 nickel modified with nitrogen and cerium. It calls for 600 MPa minimum tensile, 310 MPa minimum yield, 40 % minimum elongation and 50 % minimum reduction of area.
Check the silicon range when ordering. A182 F45 is 1.40 to 2.00 %, narrower than the 1.10 to 2.00 % that A240 allows for plate.
Is UNS S30815 the same as 253MA or 1.4835?
They cover the same grade. S30815 is the standardised designation, EN 1.4835 named X9CrNiSiNCe21-11-2 is the European number and SS 2368 the Swedish one. 253MA and 2111HTR are proprietary designations, 253MA originating with Outokumpu, formerly Avesta. No BS, En or JIS equivalent is listed in the usual comparison tables, and those tables are approximate rather than contractual.
S30815 or Grade 310, which should I use?
It turns on the atmosphere. S30815 is stronger at temperature and gives superior service in carbon, nitrogen and sulphur bearing atmospheres, partly because lower nickel helps in reducing sulphide conditions. Grade 310 wins where a carburising atmosphere needs higher nickel. Above roughly 1100 to 1150 °C, neither is suitable and a nickel alloy is required.
Can the grade be hardened by heat treatment?
No. Properties come from solution treatment at 1050 to 1150 °C with rapid cooling. Cold work will raise strength, but material cold worked 10 to 20 % should be solution treated again to recover creep strength in service.
Will it stand up to seawater or chlorides?
Not reliably. Pitting resistance only approximates Grade 316, and the high carbon leaves it open to sensitisation from welding or service exposure, with the sensitising range running 425 to 860 °C. For chloride, seawater or stress corrosion service, use a duplex grade such as F51 or F53, or a 6 % molybdenum grade such as F44.
What is the largest S30815 forging you can make?
The limits are set by the plant, not the grade. Maximum heat size is 60 t and maximum single forged piece is 30 t. Rings roll to 6,000 mm outside diameter on the 6 m radial-axial mill. Shafts turn to 14,000 mm length, discs to 5,000 mm machined diameter, and bored cylinders to 1,600 mm diameter by 10,000 mm.
What quantity do you accept and how long does it take?
Minimum order is 10 kg with no minimum piece count, so one prototype piece is workable. Lead time is 20 to 60 days depending on material availability, forging ratio, heat treatment and testing scope. Send the drawing, or the ring and disc dimensions, to sales@steelforgepieces.com or call +86-189-2135-9659 for a firm price and schedule.
Related Grades
Price a UNS S30815 Forging
Send a drawing, or just the outside diameter, inside diameter, height and quantity. You will get back the forged weight, the melt and forging route, the heat treatment plan, the testing scope and a price.
Jiangyin Jiangnan Metal Co., Ltd.
No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu, China
Composition and property limits on this page follow ASTM A182 / A182M Grade F45 and ASTM A240 / A240M Grade S30815. Heat resistance, physical property, welding and equivalence data follow published grade data sheets for S30815 and EN 1.4835. Figures are given for guidance and do not replace the specification named on an order.