Insulated ceramic matrix composite and method of manufacturing
View Patent ↗A composite material ( 10 ) formed of a ceramic matrix composite (CMC) material ( 12 ) protected by a ceramic insulating material ( 14 ). The constituent parts of the insulating material are selected to avoid degradation of the CMC material when the two layers are co-processed. The CMC material is processed to a predetermined state of shrinkage before wet insulating material is applied against the CMC material. The two materials are then co-fired together, with the relative amount of shrinkage between the two materials during the firing step being affected by the amount of pre-shrinkage of the CMC material during the bisque firing step. The shrinkage of the two materials during the co-firing step may be matched to minimize shrinkage stresses, or a predetermined amount of prestress between the materials may be achieved. An aluminum hydroxyl chloride binder material ( 24 ) may be used in the insulating material in order to avoid degradation of the fabric ( 28 ) of the CMC material during the co-firing step.
1. A material adapted for use in a high temperature environment comprising:
an oxide-oxide ceramic matrix composite material;
a layer of ceramic insulating material bonded to a surface of the ceramic matrix composite material, the insulating material further comprising:
a plurality of hollow particles, each particle in contact with at least one other of the particles; and
an aluminum hydroxyl chloride binder at least partially filling gaps between the particles.
2. The material of claim 1 , further comprising an oxide filler material dispersed among the particles, the binder at least partially filling gaps between the particles and the filler material.
3. The composite material of claim 1 , wherein the particles comprise a close packed array of hollow oxide-based spheres with each sphere in contact with a plurality of other of the spheres.
4. The composite material of claim 1 , wherein the particles each comprise a hollow sphere formed of a wall material comprising 82% mullite spheres and 18% alumina.
5. The composite material of claim 1 , further comprising a layer of adhesive disposed between the ceramic matrix composite material and the ceramic insulating material.
6. The composite material of claim 1 , wherein the ceramic matrix composite material comprises fibers comprising alumina and silica disposed in an alumino-silicate matrix.
7. The composite material of claim 1 , wherein the ceramic matrix composite material comprises fibers comprising alumina and silica disposed in an alumina matrix.
8. A material adapted for use in a high temperature environment comprising:
a plurality of hollow oxide-based particles of various dimensions;
an aluminum hydroxyl chloride binder at least partially filling gaps between the particles;
whereby the particles are situated in the binder such that each particle is in contact with at least one other particle.
9. The material of claim 8 , further comprising an oxide filler material dispersed among the particles, the binder at least partially filling gaps between the particles and the filler material.
10. The material of claim 8 , wherein the particles comprise a close-packed array of hollow oxide-based spheres.
11. The material of claim 8 , wherein the particles each comprise a hollow sphere formed of a wall material comprising 82% mullite spheres and 18% alumina.