材料期刊网

The oxidation of the ternary alloy Ni-15Cu-5Al in 1 X 10(5) Pa pure oxygen at 700 degreesC and 800 degreesC was studied. The results show that the behavior of the Ni-rich alloy is similar to that of the binary Ni-Al alloy with the same Al content in the form of an external NiO layer coupled to the internal oxidation of aluminium. The presence of 15 % (mole fraction) Cu cannot modify substantially the values of relevant parameters affecting the transition from the internal to the external oxidation of aluminium. The presence of 5 % Al reduces the oxidation rate of the corresponding Ni-Cu alloy during the whole oxidation stages, though 5 % Al is still insufficient to form protective external alumina scales.