Determination of the γ'-solvus temperature of two commercial wrought Ni-base superalloys by thermal expansion measurements

Abstract

The γ'-solvus temperatures of two commercial wrought Ni-base superalloys, i.e, WASPALOY and NIMONIC® alloy 80A, were determined independently by differential thermal analysis (DTA), measurement of the coefficient of thermal expansion (CTE) and by standard metallographic techniques. Special attention was paid to the effects of repeated cycles, and heating and cooling rates when measuring inflection points indicative of the respective transus temperatures. The results of the various independent techniques are compared and their industrial relevance is discussed.