Patent attributes
An airfoil assembly includes at least one airfoil that has a hollow interior. First and second platforms are disposed between the airfoil. At least one tie-spar extends along an axis through the first platform, the hollow interior of the airfoil, and the second platform. There is a thermal expansion difference between a thermal expansion of the tie-spar in the axial direction and the combined thermal expansion of the airfoil and the first and second platform in the axial direction. At least one spacer portion is arranged on the tie-spar. The spacer portion has a thermal expansion in the axial direction that is greater than the thermal expansion difference such that the spacer portion maintains the tie-spar under tension and clamps the first and second platforms on the airfoil.
