Tool for simultaneous local stress relief of each of a multiple of linear friction welds of a rotor forging

A method for heat treating a rotor hub, the method comprising:

• enclosing a predetermined area around a linear friction weld of an airfoil on each of a multiple of stubs of a stub-containing rotor hub forging with an upper heat treat fixture portion and a lower heat treat fixture portion by moving the upper heat treat fixture portion and the lower heat treat fixture portion toward each other along an axis of the rotor hub until the predetermined area is enclosed by a combination of the upper heat treat fixture portion and the lower heat treat fixture portion;
• and
• concurrently stress relieving the linear friction welds with the upper heat treat fixture portion and the lower heat treat fixture portion within the predetermined area while ensuring that an inner diameter of the rotor hub does not exceed a predetermined temperature wherein the upper heat treat fixture portion and the lower heat treat fixture portion move along a columnar track defined along the axis, the columnar track having a through-wall helical slot;
• and wherein a support structure is engaged with the helical slot to translate and rotate the upper and the lower heat treat fixture portions along the axis, the support structure comprises a collar assembly with a carrier that rides along an outer surface of the columnar track and a connecting arm that extends from the carrier through the through-wall helical slot.