Crack formation in iron-nickel alloys under stress in alkaline media

The corrosion resistance and the character of crack formation in iron, nickel, and iron-nickel alloys under stress in a boiling NaOH solution were studied. The character of fracture of two-phase alloys was found to be related to the presence of an -phase at the grain boundaries. In the absence of the ferrite constituent, Fe-Ni alloys fail by intercrystalline fracture and the time-to-rupture decreases with increasing stacking fault density.