Stainless Steel 310S

Stainless Steel 310S is a premium high-heat austenitic alloy. With 24–26% Cr and 19–22% Ni, it resists oxidation up to 1150°C. Low carbon (≤0.08%) prevents intergranular corrosion, making it top for ultra-high-heat industrial use.

Chemical Composition (Key, % ASTM A240)

C: ≤0.08; Cr: 24.0–26.0; Ni: 19.0–22.0

Si: ≤1.50; Mn: ≤2.00

Mechanical Properties (Annealed)

Tensile Strength: ≥515 MPa; Yield Strength: ≥205 MPa

Elongation: ≥40%; Hardness: ≤217 HB

Performance & Uses

Advantages: 1150°C service temp, excellent creep resistance, resists mild acids/alkalis.

Applications: Kiln liners, jet exhausts, furnace belts, high-temp reactors.

Equivalent Grades

EN 1.4845, JIS SUS310S, DIN X2CrNi25-21

Q&As

Why 1150°C resistance?High Cr forms a self-healing Cr₂O₃ layer. Ni stabilizes austenite (avoids brittleness). Low C stops Cr carbide formation, keeping the oxide layer strong-unlike lower alloys (309S max 980°C).

What is creep resistance?It resists slow deformation under high heat/stress. Ni slows atom movement, and fine grains reduce sliding. For a furnace belt at 1000°C, 310S sags 50% less than 309S, lasting years longer.

Corrosion beyond high heat?Good for mild corrosives (dilute acids, atmospheres) but no Mo-pits in saltwater. Avoid concentrated acids or sulfur gases (form brittle sulfides). Use for high-heat, low-chloride settings.

Welding challenges?Risk of hot cracking (narrow solidification range). Use low-S 310S filler, low heat input, and argon shielding. Clean welds (grind/pickle) to remove oxide-restores corrosion resistance.

Why more expensive than 304/309S?More Ni/Cr (costly metals). Justified for ≤1150°C: e.g., jet parts (cheaper than exotic alloys) or kilns (lasts 2–3x longer than 309S). Wasteful for low-heat use (304 is cheaper).