Patent ID: 8721292

Claim:
A gas-turbine rotor comprising: a blade disk having a center axis to coincide with a longitudinal axis of a gas-turbine and a circumferential slot with a radially inwardly facing surface, the circumferential slot extending around at least a majority of a circumference of the blade disk; a rotor blade having a blade root positioned in the circumferential slot; first and second adjoining surfaces positioned on the blade root locating the blade root in the circumferential slot, the first adjoining surface being substantially parallel to the center axis of the blade disk and the second adjoining surface being aligned to be essentially normal to a plane formed by the center axis and radius extending through the center axis and a center of the blade root, the second adjoining surface also being essentially normal to the adjoining surface ; and a stress-relieving transition area positioned between the first and second adjoining surfaces shaped as a beveled, plane edge; the second adjoining surface facing radially outwardly and engaging the radially inwardly facing surface of the blade disk to radially locate and retain the blade root in the blade disk; wherein the edge has an essentially constant width over its entire surface; wherein the edge is oriented at an angle of essentially 45°to the respective adjoining surfaces.