Abstract: An inertia welding method includes: mounting two workpieces in an inertia welding apparatus; rotating a least one of the workpieces, so as to produce relative rotation of the two workpieces at a predetermined RPM; forcing together the two workpieces with predetermined first weld load so as to cause frictional heating at an interface therebetween; maintaining the first weld load for a first interval; forcing together the two workpieces with a predetermined second weld load greater than the first weld load so as to cause material upset and bonding between the two workpieces, while the rotation brakes to a stop, terminating the weld process; wherein the first and second weld loads are selected so as a produce a specific temperature-distance profile in a selected one of the workpieces, at the termination of the weld process.

Abstract: Damage in a blisk airfoil is machined away to create a notch. A repair is welded in the airfoil to fill the notch. The weld repair is then machined to restore the airfoil to a substantially original, pre-damaged configuration at the repair.