The effect of dispersed oxides on the oxidation behavior of Al-and Ti-Containing Ni-20 pct Cr alloys

The effect of dispersed Y₂O₃ and La₂O₃ on the isothermal and cyclic oxidation behavior of Al- and Ti-containing Ni-20Cr alloys has been investigated. It has been found that the dispersolids improve the oxidation resistance of these alloys, but this improvement is less than that observed in aluminum- and titanium-free Ni-20Cr alloys. The oxidation resistance imparted by the presence of the dispersoids was found to increase as the aluminum and titanium contents were decreased. It is proposed that these changes in oxidation resistance arise from differences in the extent of subscale attack, oxidation induced alloy porosity and internal oxidation.