254 SMO® Super Austenitic Stainless Steel Bar

UNS S31254

254 SMO® stainless steel bar, also known as UNS S31254, was originally developed for use in seawater and other aggressive chloride-bearing environments. This grade is considered a very high end austenitic stainless steel; mainly comprised of between 19.5% and 20.5% chromium, 17.5% to 18.5% nickel, 6% to 6.5% molybdenum and .18% to .22% nitrogen. These specific levels of Cr, Ni, Mo, and N in this “super austenitic” chemical makeup allow 31254 to combine impact toughness resistance to corrosion cracking, with pitting and crevice corrosion resistance. The result is strength of nearly twice that of 300 series stainless steels.

UNS S31254 is often referred to as a “6% Moly” grade due to the molybdenum content; the 6% Moly family has the ability to withstand high temperatures and maintain strength under volatile conditions. This grade has surpassed its original intent and overlapped into many industries proving useful owing to its high level of molybdenum amount other elements, which allows 31254 to be used successfully in various applications such as Flue gas desulfurization and Chemical environments.

Industries that use 31254 include:

  • Chemical
  • Desalination
  • Flue gas desulfurization
  • Food processing
  • Pharmaceutical
  • Pulp and Paper

Products partially or completely constructed of 31254 include:

  • Chemical processing equipment
  • Desalination equipment
  • Flue gas desulfurization scrubbers
  • Food processing equipment
  • Heat exchangers
  • Hydrometallurgy
  • Oil and gas production equipment
  • Pulp mill bleach systems
  • Seawater handling equipment
  • Tall oil distillation columns and equipment
Stocking Diameters 1” to 11”
Material Lengths Up to 24’
Bar Specifications
Uns Type Ams Astm Federal Characteristics
S31254 254 SMO® A-276
A-484
A-479
A high end austenitic stainless steel with strength nearly twice that of 300 Stainless steel series.
Chemistry Analysis
C MN P S SI CR NI MO CU OTHER M/NM
.02 1. Max .03 Max .01 Max .80 Max 19.5 – 20.5 17.5 – 18.5 6 – 6.5 .5 – 1. NM

254 SMO® is a trademark of Avesta.
The information above is not warranted, guaranteed, or for design purposes.

The information above is not warranted, guaranteed, or for design purposes.

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