Effect of Aging Treatment on Intergranular Corrosion Properties of Ultra-Low Iron 625 Alloy

Table 1

The main phases occurring in long-term aging nickel-based superalloy.

Phase	Structure	Typical Composition
′′	body-centered tetragonal	Ni3(Nb>0.5,Ti<0.5,Al<0.5,Mo<0.5)
δ	orthorhombic	Ni3Nb
MC	cubic	(Nb,Ti)C
M6C	cubic	(Cr>0.2,Mo>0.2,Fe)C
M23C6	cubic	(Cr>0.8,Fe,Mo)C
Laves	MgZn2-Types(AB2)	TiFe2, NbFe2, MoFe2, etc.
	Hexagonal(B7A6)	Fe7Mo6, Fe7Nb6, Fe7Mo6, etc
	Tetragonal(BA)	: FeCr, MoFe, NbFe, etc.