A Current T-T-T Diagram for Wrought Alloy 718

A T-T-T study was carried out on the phase reactions in high quality wrought alloy 718 billet.Samples were exposed from 12OO'F to 17OO'F for times of 0.1 hour to 50 hours.The only phases found and plotted on the T-T-T diagram were f/.f. and delta phases.The ?/, 1/', delta, aCr, and sigma phases found in a previous longtime study were plotted as extensions on the same T-T-T diagram.In longtimes and under stress, the transition of 1/' to f + delta occurs below 1200°F.* Berrita, USA.