The Home of HASTELLOY® and HAYNES® alloys

Principal Features

Outstanding Corrosion Resistance, High Strength

HASTELLOY® C-22HS®alloy** (UNS #N07022) is corrosion-resistant, nickel-chromium-molybdenum alloy which can be heat treated to obtain a strength approximately double that of other C-type alloys. Importantly, the corrosion resistance and ductility of the alloy remain excellent when in the high strength condition. In addition to its high uniform corrosion resistance in oxidizing as well as reducing environments, the as-heat treated C-22HS alloy possesses high resistance to chloride-induced pitting and crevice corrosion attack.

Product Forms

C-22HS alloy is available in the form of plate, sheet, strip, billet, bar, wire, pipe, and tube.

Heat Treatment

The high strength of C-22HS alloy is derived from the formation of strengthening particles of Ni2(Mo,Cr) which form during the patented*** two-step age-hardening heat treatment. The approximately 48 hour heat treatment, 1300°F (705°C) FC to 1125°F (605°C)/32 hours/AC, is described in more detail on page 14.

Solution Annealed and Filler Wire Applications

C-22HS alloy may also be considered for applications which do not require the high strength imparted by the heat treatment. In the annealed condition, C-22HS alloy has even higher corrosion-resistance, particularly with regard to localized corrosive attack. This localized attack resistance also makes the alloy an attractive candidate as a general-purpose filler metal or weld overlay.


  • Agitators and blenders
  • Shafting
  • Fan blades and hubs
  • Fasteners
  • Springs
  • Valves
  • Dies
  • Screws
  • Wellhead parts
  • Rings and gaskets

Field Test Program

Samples of C-22HS alloy in the age-hardened condition are available for field trials. Furthermore, samples can be weighed prior to delivery, and then reweighed after test by the customer, and reports provided on corrosion rates and other observations. For samples, please contact one of the Haynes International Service Centers listed on the back cover of this brochure.

** Covered by U.S. Patent 6,860,948
*** Covered by U.S. Patents 6,544,362 and 6,638,373

Download Page Download Brochure