Delta Phase in INCONEL 718: Mechanical Properties and Forging Process Requirements

To fullfill the Inconel 718 requirements, it is necessary to understand the influence of delta phase on microstructure evolution and on mechanical resistance. Therefore three comprehensive studies have been carried out: a validated delta phase characterization methodology, of the ' effects of (con~entr/emvology) on mecmhaa?cal properties: delta phase delta content affects yield strength and both content and morphology affect creep rupture properties, a validated delta solutionning model predicting content evolution and a study pointing out the parameters of delta particles pinning the grain boundary. Superalloys 718,625,706 and Various Derivatives Edited by B.A. Loria The Minerals, Metals&Materials Society, 1994