A structurally-reinforced rotor disk for a gas turbine engine is disclosed. The rotor disk may comprise a body including a rim configured to support airfoils (which may be separate or integral with the airfoils), an axially-extending bore disposed radially inward of the rim, and a radially-extending web connecting the rim and the bore. The bore may include an axial outer edge and at least one circumferentially-extending annular recess formed axially between the outer edge and the web. The rotor disk may further comprise an annular ring retained in the annular recess, and the annular ring may be formed from a different material than the body of the rotor disk so as to increase a self-sustaining radius of the rotor disk.