Strain induced γ′ precipitation in nickel base superalloy Udimet 720 using a stress relaxation based technique

The influence of 5% prestain on γ′ precipitation during high temperature deformation of Udimet 720 was studied using stress relaxation. The occurrence of a stress plateau was associated with γ′ precipitation and verified by metallography examination. PTT diagram was determined for the alloy and related to the diffusion coefficient of γ′ forming elements.