Project Description

Alloy 33 (UNS N08033/R20033)

Alloy 33 (UNS N08033/R20033) is a high-chromium austenitic alloy which combines ease of fabrication with outstanding resistance to highly oxidizing media such as concentrated sulphuric acid. Despite its low molybdenum content, it shows excellent resistance to localized corrosion in halide media. The nitrogen content ensures high mechanical properties with good ductility. Alloy 33 is a material that can be used for many applications in the chemical processing industry.

Equivalent Grades

Nicrofer 3033NS1405Alloy 33N08033
X1NiCrMoCuN 33-32-11.4591X1NiCrMoCuN 33-32-1

Product Forms

Wire, Bar, Strip, Sheet, Plate, Tube, Pipe, Pipe Fittings, Forgings

Chemical Composition,%


Typical Physical & Mechanical Properties (RT, Solution Annealed)

Density, g/cm3Melting Point, ℃Tensile Strength, MPaYield Strength, MPaElongation,%


Rod, Bar, Wire, ForgingsASTM B516, ASME SB516, ASTM B649, ASME SB649
Plate, Sheet, StripASTM B516, ASME SB516, ASTM B649, ASME SB649
OthersASTM B366/ASME SB366(Fittings)


  • Excellent resistance against pitting corrosion in media containing chloride and against general corrosion in hot mineral acids, mixed acids and alkalis as well as seawater and brackish water
  • High strength and high ductility even in high temperatures
  • Good workability and welding characteristics,
  • ASME approval for pressure vessels in the temperature range from -196℃ to 450℃.


  • Heat recovery and distribution systems in the sulfuric acid production
  • Pipes and heat exchangers for sulfuric acids contaminated with chlorides
  • Vessels for storage and transport of nitric acid/hydrofluoric acid mixtures
  • Seawater conducting pipes, condensers, coolers, etc. with excellent resistance against pitting corrosion
  • Production and use of NaOH and KOH up to 70 wt.-% and max. 170℃
  • Urea solutions in the concentration range from 5 to 90 wt.-%
  • Components for the pulp and paper industry
  • Vessels and pipes in purified terephthalic acid (PTA) plants