METHOD OF MANUFACTURING AND REFINISHING INTEGRALLY BLADED ROTORS

A method of forming integrally bladed rotors for gas turbines is described. The method includes drilling in a workpiece material recesses defining flow passages and rotor blades, performing a coarse milling step to refine surfaces of the rotor blades, and filling the recesses between the rotor blades with a damping material, thus encasing the rotor blades in the damping material. The method further includes performing a finishing milling step to remove the damping material and the workpiece material on surfaces of the rotor blades, while maximizing a damping effect of the damping material on the rotor blades. To maximize the damping effect, the finishing milling tool moves along a path that preferentially mills one surface of a blade while the other surface is in contact with the damping material.