High Nickel Alloys & Superalloys

This group of alloys are used for their outstanding corrosion and high temperature resistance.  Many are metallurgically related to the austenitic stainless steels but are much more highly alloyed, particularly with nickel, chromium and molybdenum in order to enhance their corrosion resistance.  These alloys are used resist extremely corrosive conditions in the energy, power, chemical and petrochemical industries.

The term “superalloy” is applied to alloys which have outstanding high temperature strength and oxidation resistance.  The nickel-based superalloys contain carefully balanced alloying additions of chromium, cobalt, aluminium, titanium and other elements.  Often components are produced by carefully controlled solidification in order to get an optimum directionally solidified or even single crystal structure.  These components can have strengths at 1000°C which exceed that of ordinary steels at room temperature.  They are essential in the hottest parts of gas turbines both for power generation and aircraft.

Details of applications can be found under the relevant headings in the Materials Selection & Use section.

Details of mechanical properties, corrosion resistance and fabrication can be found in the following publications.  Note that some are now old but remain good collections of data.

  • 10086  Corrosion-and-Heat-Resistant Nickel Alloys: Guidelines for Selection and Application
  • 11008  Machining Nickel Alloys
  • 14048  Nickel, Nickel Everywhere
  • 393  High-Temperature High-Strength Nickel-Base Alloys
  • 11012  Guidelines for the Welded Fabrication of Nickel Alloys for Corrosion-Resistant Service
  • 10056  Practical Guide to High-Temperature Alloys
  • 534  Machining and Grinding Several Cast Nickel-Base High-Temperature Alloys
  • 9004  High-Temperature Characteristics of Stainless Steel
  • 266  Heat-Resistant Castings, Corrosion-Resistant Castings, Their Engineering Properties and Applications
  • 1196  Cast Heat-Resistant Alloys