Specialty Stainless Steels

Duplex Stainless Steels have a structure that contains both ferrite and austenite. Duplex alloys have higher strength and better stress-corrosion cracking resistance than austenitic steels and greater toughness than ferritic alloys, especially at low temperatures. The corrosion resistance of duplex alloys depends primarily on their composition, especially the amount of chromium, molybdenum, and nitrogen they contain.

Precipitation-Hardening Stainless Steels contain chromium and nickel as the predominant alloying elements. They are designed to be formable in the solution-annealed condition. The addition of elements such as copper, aluminum, titanium and molybdenum allows these alloys to be hardened by heat treatment to strength levels several times that of Type 304. Precipitation-hardening stainless steels may be martensitic or semi-austenitic. Corrosion resistance is usually better than that of straight chromium ferritics.

Superaustenitic Stainless Steels are austenitic alloys that contain higher levels of elements such as chromium, nickel, molybdenum, copper, and nitrogen. This results in superior strength and corrosion resistance.