US 12,435,008 B2
Auxetic materials and structures for ceramic matrix composite airfoil mandrels
David J. Wasserman, Hamden, CT (US); and James T. Roach, Vernon, CT (US)
Assigned to RTX Corporation, Farmington, CT (US)
Filed by RTX Corporation, Farmington, CT (US)
Filed on Sep. 21, 2023, as Appl. No. 18/371,070.
Prior Publication US 2025/0100941 A1, Mar. 27, 2025
Int. Cl. C04B 35/80 (2006.01); B64C 1/00 (2006.01); C04B 35/628 (2006.01); C04B 35/64 (2006.01); C04B 35/657 (2006.01)
CPC C04B 35/80 (2013.01) [C04B 35/62873 (2013.01); C04B 35/62884 (2013.01); C04B 35/64 (2013.01); C04B 35/657 (2013.01); B64C 1/00 (2013.01); B64C 2001/0072 (2013.01); C04B 2235/422 (2013.01); C04B 2235/5244 (2013.01); C04B 2235/5256 (2013.01); C04B 2235/6028 (2013.01); C04B 2235/614 (2013.01); C04B 2235/616 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A method of fabricating a ceramic matrix composite component, the method comprising:
fabricating a ceramic preform, the preform comprising a hollow portion with an internal cavity extending along a first axis from a first end to a second end of the hollow portion;
supporting the hollow portion with an auxetic mandrel disposed within and the internal cavity and coaxial with the hollow portion, the auxetic mandrel comprising a first mandrel end and a second mandrel end;
at least partially densifying the preform with a matrix; and
removing the auxetic mandrel from the internal cavity by:
simultaneously applying a compressive force to each of the first mandrel end and the second mandrel end creating a deformed auxetic mandrel to reduce a cross-sectional profile of the auxetic mandrel along a second axis orthogonal to the first axis; and
extracting the deformed auxetic mandrel from the first end of the hollow portion.