What is 1.4845 Stainless Steel?

1.4845 stainless steel, commonly known as 310S or UNS S31008, is a high-alloy austenitic stainless steel with exceptional high-temperature oxidation resistance and creep strength. With its high chromium and nickel content, it is designed for continuous service at temperatures up to 1150°C, making it a premier material for furnace components, heat treatment equipment, and high-temperature industrial processes.

 

This high-temperature resistant grade is standardized under key international designations.

Standard	Equivalent Grade
EN (Europe)	1.4845
ASTM/AISI (USA)	310S, UNS S31008
JIS (Japan)	SUS310S
KS (Korea)	STS310S

Its composition is rich in chromium and nickel to resist oxidation and maintain strength at high temperatures.

Element	C	Si	Mn	P	S	Cr	Ni
Content (%)	≤ 0.08	≤ 1.5	≤ 2.0	≤ 0.045	≤ 0.03	24.0 - 26.0	19.0 - 22.0

It maintains good mechanical properties at both room and elevated temperatures.

Property	Yield Strength (Rp0.2)	Tensile Strength (Rm)	Elongation (A)	Hardness (HB)
Typical Value	≥ 205 MPa	500 - 750 MPa	≥ 40%	≤ 215

 

Key Characteristics and Applications of 1.4845 / 310S

Exceptional High-Temperature Oxidation Resistance: Forms a stable, adherent chromium oxide layer that protects against scaling and oxidation in continuous service up to 1150°C and intermittent service up to 1050°C.

High Creep and Rupture Strength: Maintains structural integrity under mechanical load at elevated temperatures better than most standard austenitic grades.

Good Sulfur Resistance: Performs well in atmospheres containing sulfur compounds, which can degrade many other stainless steels.

 

Primary Applications:

Heat Treatment Furnaces: Radiant tubes, muffles, retorts, baskets, and furnace rolls.

Chemical & Petrochemical: Reformers, pyrolysis tubes, and catalyst support grids in high-temperature processes.

Power Generation: Boiler components, superheaters, and heat recovery systems.

Glass & Ceramic Manufacturing: Hot handling equipment and kiln furniture.

 

How does 310S (1.4845) compare to 309S (1.4833) in high-temperature service?
Both are high-temperature grades, but 310S contains significantly more chromium and nickel (typically 25% Cr, 20% Ni vs. 23% Cr, 13% Ni in 309S). This gives 310S superior oxidation resistance and higher temperature capability-continuous use up to ~1150°C for 310S vs. ~1050°C for 309S. 310S also has better carburization resistance. 309S is often used as a cost-effective option for slightly less severe conditions or as a welding filler for joining dissimilar metals.

 

What are the limitations of 310S stainless steel?
While excellent in oxidizing and sulfur-containing atmospheres, 310S has limited resistance to reducing environments and halogen gases. Its high nickel content makes it more expensive than standard grades. It can also be prone to sigma phase formation if held in the temperature range of 650-900°C for prolonged periods, which can embrittle the material. Proper heat treatment and controlled cooling are important to maintain ductility.

 

Looking for a Reliable Supplier of 1.4845 / 310S Stainless Steel?
GNEE Steel supplies premium high-temperature grade 310S (1.4845) stainless steel in plate, sheet, pipe, and bar forms for demanding furnace and process applications. We provide full material traceability and certification to ensure performance in extreme conditions. If you have any requirements, please feel free to contact us.