Abstract
The corrosion behavior of nickel base heat resisting alloys is investigated in steam at 800°C and 40 atm, simulating the superheated steam of the nuclear steelmaking system. The alloys tested are five new alloys developed for the nuclear steelmaking system and one commercial alloy, Inconel 617.
A protective surface oxide scale, consisting of Cr2O3 mainly and of MnCr2O4, forms on all of the alloys except Inconel 617. Internal oxides, consisting of Al and Ti oxides, also form in the alloys containing Al. For Inconel 617, nodular oxides, consisting of NiO in the outer layer and Cr oxide in the inner layer, form in addition to Cr2O3 and MnCr2O4 after 1 000 h.
