Investigation of heat treatment parameters effect on the microstructure and on the mechanical properties of a powder metallurgy nickel-base superalloy

Abstract : The relationships between heat treatment parameters and microstructure, and between microstructure and mechanical properties were investigated in the SMO43 disc P/M superalloy. Various heat treatments were applied to this superalloy to determine the effect of the solution temperature on the grain size, and of the cooling path and aging temperature on the ' precipitates distribution. Microstructural features were characterised through the careful study of ' precipitation. Fatigue crack growth tests with dwell time were performed at high temperature for comparison of the mechanical properties of some selected microstructures.