Brake assembly having multi-piece core and replaceable friction surfaces

1. A method comprising:

determining a required shape of a discrete, annular, carbon-carbon composite article;

forming a plurality of non-annular preforms configured to be assembled into an annular shape;

densifying the plurality of non-annular preforms to form a plurality of densified non-annular preforms; and

assembling the plurality of densified non-annular preforms to form the discrete, annular, carbon-carbon composite article.

2. The method of claim 1 , wherein forming a plurality of non-annular preforms comprises forming a plurality of substantially identical non-annular preforms.

3. The method of claim 1 , wherein assembling the plurality of densified non-annular preforms comprises inserting a projection of a first one of the plurality of densified non-annular preforms into a complementary opening in a second one of the plurality of densified non-annular preforms.

4. The method of claim 1 , wherein forming a plurality of non-annular preforms comprises forming a plurality of substantially identical non-annular preforms each having at least one projection and at least one opening complementary to the at least one projection, and wherein assembling the plurality of densified non-annular preforms comprises inserting the at least one projection of a first one of the plurality of densified non-annular preforms into the complementary opening in a second one of the plurality of densified non-annular preforms.

5. The method of claim 1 , wherein the discrete annular carbon-carbon composite article comprises a first annular portion having a first thickness and a second annular portion having a second thickness greater than the first thickness, further comprising forming a first annular preform having the shape of the first annular portion and densifying the first annular preform, wherein assembling the plurality of densified non-annular preforms comprises assembling the plurality of densified non-annular preforms onto an inner or an outer periphery of the first annular preform to form the discrete annular carbon-carbon composite article.

6. The method of claim 5 , wherein densifying the first annular preform comprises densifying the first annular preform using a first process, and wherein densifying the plurality of non-annular preforms comprises densifying the plurality of non-annular preforms using a second process different than the first process.

7. The method of claim 1 , further including mounting a first unitary annular article to a first side of the discrete carbon-carbon composite article.

8. A brake disk comprising:

an annular core comprising an annular first element having a first thickness and an inner or an outer periphery comprising a plurality of protrusions and an annular second element comprising a plurality of notches complementary to the protrusions, wherein the annular second element comprises a plurality of non-annular elements;

a first friction disk mounted on a first side of the annular core;

a second friction disk mounted on a second side of the annular core opposite from the first friction disk; and

at least one fastener connecting the first and second friction disks to the annular core.

9. The brake disk of claim 8 , wherein the annular second element comprises an inner element including a first portion having a second thickness greater than the first thickness.

10. The brake disk of claim 9 , wherein the plurality of non-annular elements are substantially identical.

11. The brake disk of claim 9 , wherein each non-annular element of the plurality of non-annular elements includes a projection and an opening complementary to the projection, wherein the projection of a first one of the plurality of non-annular elements is configured to be received in the opening of a second one of the plurality of non-annular elements.

12. The brake disk of claim 8 , wherein the annular core is formed of a carbon-carbon composite material.

13. The brake disk of claim 8 , wherein the first and second friction disks are formed from carbon-carbon composite material.

14. A method of assembling a carbon-carbon composite brake disk, the method comprising:

forming a plurality of non-annular preforms comprising notches and configured to be assembled into an annular shape;

densifying the plurality of non-annular preforms to form a plurality of densified non-annular elements;

placing a first annular friction disk in a restraint fixture;

placing on the first annular friction disk in the restraint fixture an annular core element including a plurality of protrusions having a shape along an inner or an outer periphery of the annular core element;

placing the plurality of densified non-annular elements into the restraint fixture with the notches engaging the protrusions to form the annular shape;

placing a second annular friction disk on the annular core element; and

connecting the first and second friction disks.

15. The method of claim 14 , wherein the protrusions of the annular core element are located on an inner periphery of the annular core element, and wherein placing the plurality of densified non-annular elements into the restraint fixture comprises placing the plurality of densified non-annular elements around the inner periphery of the annular core element with the notches engaging the protrusions.

16. The method of claim 14 , wherein the protrusions of the annular core element are located on an outer periphery of the annular core element, and wherein placing the plurality of densified non-annular elements into the restraint fixture comprises placing the plurality of densified non-annular elements around the outer periphery of the annular core element with the notches engaging the protrusions.

17. The method of claim 14 , further including:

removing one of the first or second friction disks;

inspecting the plurality of densified non-annular elements for damage; and

replacing one or more of the plurality of non-annular elements showing damage with a respective undamaged, densified non-annular elements.