Weldability of Ni-based superalloys

This paper reviews the inherent weldability of precipitation hardening Ni-based superalloys commonly used in structural components of aircraft engines. Weldability often refers to alloys resistant to cracking during welding which for superalloys is difficult to comprehend since specific liquation and cracking mechanism may differ in this class of materials. A new procedure of evaluating the weldability as well as susceptibility towards strain age cracking of these alloys is proposed in which standard metallographic examinations are used to understand the cracking mechanisms in parallel with systematic ductility measurements such as Varestraint or Gleeble testing.

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