Seal seat insert for gas turbine engines

1. A seal assembly for a gas turbine engine, the seal assembly comprising:

a seal body coupled to an engine static structure of the gas turbine engine; and

a seal seat insert coupled to a radially extending portion of a shaft of the gas turbine engine;

wherein the seal body is configured to be biased into contact with the seal seat insert to provide a sealing pressure between the seal body and the seal seat insert,

wherein the seal seat insert is made from a ceramic matrix composite including at least one of silicon carbide and silicon nitride, and

wherein the radially extending portion of the shaft directly contacts around the seal seat insert.

2. The seal assembly of claim 1 , wherein the seal seat insert is made from a ceramic material.

3. The seal assembly of claim 1 , wherein the seal body contains graphite.

4. The seal assembly of claim 1 , wherein the seal seat insert is retained within a recess defined by the radially extending portion of the shaft.

5. The seal assembly of claim 4 , wherein the seal seat insert is retained within the recess using an interference fit.

6. A bearing assembly for a gas turbine engine comprising:

an engine static structure;

a shaft configured to rotate within the gas turbine engine;

a bearing supporting the shaft relative to the engine static structure;

a seal body coupled to the engine static structure; and

a seal seat insert coupled to a radially extending portion of the shaft;

wherein the seal body is configured to be biased into contact with the seal seat insert to provide a sealing pressure between the seal body and the seal seat insert, wherein the seal seat insert is made from at least one of silicon carbide and silicon nitride, and

wherein the radially extending portion of the shaft directly contacts around the seal seat insert.

7. The bearing assembly of claim 6 , wherein the seal seat insert is made from a ceramic material.

8. The bearing assembly of claim 6 , wherein the seal seat insert is made from a ceramic matrix composite.

9. The bearing assembly of claim 8 , wherein the seal body contains graphite.

10. The bearing assembly of claim 6 , wherein the seal seat insert is made from at least one of silicon carbide and silicon nitride.

11. The bearing assembly of claim 6 , wherein the seal seat insert is retained within a recess defined by the radially extending portion of the shaft.

12. The bearing assembly of claim 11 , wherein the seal seat insert is retained within the recess using an interference fit.

13. The bearing assembly of claim 12 , wherein the radially extending portion is attached to the shaft, wherein the recess is defined in the radially extending portion of the shaft.

14. The bearing assembly of claim 13 , wherein the recess is defined in an axially aft facing surface of the radially extending portion.

15. The bearing assembly of claim 6 , further comprising a seal holder and a biasing member, wherein the seal body is supported by the seal holder, and the seal holder is coupled to the engine static structure via the biasing member.

16. A method of forming a seal between an engine static structure and a shaft of a gas turbine engine, the method comprising:

supporting a seal body on the engine static structure;

coupling a seal seat insert to a radially extending portion of the shaft; and generating a sealing pressure via direct contact between the seal body and the seal seat insert, wherein coupling the seal seat insert to the shaft comprises retaining the seal seat insert within a recess defined by the shaft, and

wherein the radially extending portion of the shaft directly contacts around the seal seat insert.

17. The method of claim 16 , wherein the seal seat insert is made from at least one of a ceramic material and a ceramic matrix composite material.