Improvement in the Mechanical Properties and Oxidation Resistance of Dispersion Strengthened Nickel-Chromium Alloys

A dispersion strengthened nickel-base alloy, Ni/16Cr/5Al/2ThO2, exhibiting excellent high temperature oxidation resistance was subjected to a series of thermomechanical processing studies to optimize its mechanical properties. All properties with the exception of room temperature ductility were above the target specifications for the program. Extensive oxidation tests were conducted on an alternative composition, Ni/9Cr/6Al, with and without a dispersoid (ThO2) addition. The results indicated that the Ni/9Cr/6Al/2ThO2 alloy had generally poorer high temperature oxidation characteristics. The mechanical properties, however, were found to be similar to those of the Ni/16Cr/5Al/2ThO2 alloy. (Modified author abstract)