6MO / Alloy 254

6MO / Alloy 254 is a high-alloy austenitic stainless steel developed for use in seawater and other aggressive chloride-bearing media. It has a high resistance to pitting and crevice corrosion typically associated with higher alloys such as Alloy 625.

UNS: S31254
Stock Sizes: 1/4” – 1” OD


  • Seamless Tube: ASTM A213/A269
  • NACE MR0175/MR0103
  • NORSOK M-650

Available Processing:

  • Cold Worked and Bright Annealed

Common Testing: Eddy Current, Flare, Flattening, Positive Material Identification

Chemical Composition (%)

Iron (Fe)Balance
Chromium (Cr)19.5-20.5%
Nickel (Ni)17.5-18.5%
Molybdenum (Mo)6.0-6.5%
Manganese (Mn)1% Max
Silicon (Si)0.80% Max
Copper (Cu)0.50-1.00% Max
Carbon (C)0.020% Max
Sulfur (S)0.010% Max
Phosphorus (P)0.030% Max
Nitrogen (N)0.18-0.22% Max

Physical Properties

Density (lb/in3)0.289
Elongation (min %)35
Minimum Yield (psi)45,000
Minimum Tensile (psi)95,000
Max Hardness (HRB)96