Project Description

Hastelloy B-2 (UNS N10665)

Hastelloy B-2 (UNS N10665) is a solid solution strengthened, nickel-molybdenum alloy, typically used in extreme reducing conditions. Hastelloy B-2 has significantly lower carbon, silicon and iron compared to its’ predecessor, Hastelloy B (UNS N10001), making the alloy less susceptible to decreased corrosion resistance in the weld zone, in the as-welded condition. Controlling other alloying elements such as iron and chromium solved other issues concerning fabricability. Stringent chemistry control along with years of development has resulted in the alloy used today, both in Hastelloy B-2 and Hastelloy B-3 Today, Hastelloy B-2 with restricted chemistry can be used in the welded condition and is less susceptible to SCC under many conditions. As always, care must taken in selecting the right alloy for the desired application.
Hastelloy B-2 should not be used at temperatures between 1000°F and 1600°F as the alloy forms secondary phases that could decrease the ductility of the material.

Equivalent Grades

Hastelloy B-2
Nimofer 6928
NS3202Hastelloy B-2N10665NiMo282.4617NA44

Product Forms

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

Chemical Composition,%


Typical Physical & Mechanical Properties (Annealed)

Density, g/cm3Melting point, ℃Tensile strength, MPaYield strength, MPaElongation,%


Rod, Bar, Wire, ForgingsASTM B335, ASME SB335
Plate, Sheet, StripASTM B333, ASME SB333
Pipe, TubeASTM B622, ASTM B619, ASTM B775, ASME SB622, ASME SB619, ASME SB775
OthersASTM B366, ASTM B564, ASTM B462, ASME SB366, ASME SB564, ASME SB462


  • Controlling the minimum content of iron and chromium elements to prevent the formation of Ni4Mo in β phase
  • Excellent corrosion resistance to reduced environment
  • Excellent resistance to medium concentration of sulfuric acid and many non oxidizing acid corrosiveness
  • Good resistance to chloride ion reduction stress corrosion cracking (SCC)
  • Excellent ability to resist various kinds of organic acid corrosion


  • Superior resistance to hydrochloric acid, aluminum chloride catalysts and other strongly reducing chemicals.
  • Excellent high-temperature strength in inert and vacuum atmospheres.