8/8/2019 COMPOSITE MATERIALS UNIT V SSN

1/41

UNIT V

ADVANCES IN COMPOSITES

Carbon / Carbon Composites

- B. Anand Ronald

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

2/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

3/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

4/41

UNIQUE PROPERTIES OF CARBON MATRIX:

It remains solid @ higher temperatures than anyother material

Its sublimation point at atmospheric pressure isabove 3600rC and its strength increases with

temperature upto this point. It resists radiations, has high thermal emissivity

and excellent high temperature dimensionalstability.

Carbon is exceptionally inert to chemicals andreacts only at high temperatures with H2, O2, S, Cl2and F2.

It is self lubricating (because of graphite).

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

5/41

C/ C composites can withstand higher temperaturethan other materials, but in OXIDIXING Atmosphere,it oxidizes at much lower temperatures.

In metals, that withstand high temperatures a tough

oxide coating is formed on the surface in oxidizingatmosphere. This oxide layer prevents oxygen fromentering into the material and prevents furtheroxidation. Carbon does not have this ability (asoxidation products are gases CO, CO2). Therefore itmust be protected from oxidation using coatings andimpregnates that block O2 from penetrating.

The process of making C/ C composites is costly andtime consuming.

Unlike other ceramics, carbon powder is nonsinterable and therefore cannot be processed byconventional process (Pressing/ Sintering)

LIMITATIONS OF C/ C Composites:

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

6/41

Carbon-carbon composites applications in

aircraft and F1 braking

rocket motor nozzle throats and exit cones

nosetips/leading edges Re-entry thermal protection systems

Heat Shield and Nozzle for Rockets andMissiles

Bolts and nuts for graphite refractory lining Gas Turbine engine nozzles

NOTE: For CVD technique refer Chawla For Sol gel , refer my PPT

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

7/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

8/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

9/41

FABRICATION OF C/ C composites

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

10/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

11/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

12/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

13/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

14/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

15/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

16/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

17/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

18/41

Carbon - carbon exit cones for rocket motors- Snecma Propulsion Solide

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

19/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

20/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

21/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

22/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

23/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

24/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

25/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

26/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

27/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

28/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

29/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

30/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

31/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

32/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

33/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

34/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

35/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

36/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

37/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

38/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

39/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

40/41

8/8/2019 COMPOSITE MATERIALS UNIT V SSN

41/41