310 / 310S

This grade, combing excellent high temperature properties with good ductility and weldability is designed for cyclic elevated temperature service. It resists oxidation in continuous service at temperatures up to 2100⁰F provided reducing sulphur gasses are not present. It is also used for intermittent service at temperatures up to 1900⁰F because it resists rescaling and has a low co-efficient of expansion. This factor reduces the tendency of the steel to warp in heat service.

Type 310S is used when the application environment involves moist corrodents in a temperature range lower than that which is normally considered “high temperature” service.

Corrosion resistance

Excellent resistance at normal temperatures and when in high temperature service exhibits good resistance to oxidation and carburizing atmospheres. Resists fuming nitric acid at room temperature and fused nitrates up to 800⁰F.

Heat resistance

Good resistance to oxidation in intermittent service in air at temperatures up to 1900⁰F and 2100⁰F in continuous service. Good resistance to thermal fatigue and cyclic heating. Widely used where sulphur dioxide gas is encountered at elevated temperatures. Continuous use in 800 – 1575⁰F range not recommended but often performs well in temperatures fluctuating above and below this range.

Heat treatment

Annealing – heat to 1900 – 2100⁰F and cool rapidly for maximum corrosion resistance. This treatment is also recommended to restore ductility after each 1000 hours of service at 1200 – 1900⁰F.


Good characteristics suited to all standard methods. Type 310S electrodes generally recommended for fusion welding.


Typical applications

AISI analysis (%)

310.25 max2.0 max.045 max.030 max1.5 max24.0 to 26.019.0 to 22.0
310S.08 max2.0 max.045 max.030 max1.5 max24.0 to 26.019.0 to 22.0

Mechanical properties (annealed)

Yield Strength .2% Offset
Ultimate Strength
Elongation in 2”
Impact Charpy
(ft. – lbs)
Elastic modulus

Other properties

Creep Strength 1%
Flow in 10,000 h
at 1,000⁰F psi
at 200 H-Annealed
Resistivity at 68⁰F
Thermal Expansion
32⁰ – 212⁰F
Thermal Conductivity
17,5001.01788.08.0 (at 212⁰F)
10.8 (at 932⁰F)