This technical presentation summarizes ceramic composites. It begins by defining ceramics and composites. Ceramic composites have higher strength, damage tolerance, and toughness than monolithic ceramics due to reinforcement. Examples of structural ceramic composites in aerospace include rocket engine nozzles and scramjet engines. Case studies show ceramic composite armor provides ballistic impact protection while reducing weight compared to steel. Reinforcements like silicon carbide and matrices like alumina are discussed. In conclusion, ceramic composites are well-suited for applications requiring high-temperature or weight-constrained ballistic impact protection.

1. A Technical Presentation on
Ceramic Composites
By
DESHPANDE JAYDEEP SANJEEV
T.E. Mechanical
PVG’S COET, PUNE.
Under the guidance of
Prof. P.G.Kulkarni

2. Contents:
Introduction
Monolithic vs. Composite
Composites and applications
Advantages
Case Study

3. Introduction
A ceramic is an inorganic, nonmetallic
solid prepared by the action of heat and
subsequent cooling.
The word "ceramic" comes from the Greek
word κεραμικός (keramikos), "of pottery"
or "for pottery",from κέραμος (keramos),
"potter's clay, tile, pottery"

4. Introduction
Base matrix + reinforcement = composite!

5. Composite -v- Monolithic Ceramics
Interphase
LOAD
matrix
fiber
crack
crack
arrest
Fiber Composite materials, whether platelet, chopped
Matrix fiber, or continuous fiber reinforced are superior
“engineering”materials to monolithics:
• generally higher strength, especially in tension
• much higher damage tolerance (fracture toughness)

6. Composite -v- Monolithic Ceramics
200
Carbon
Fiber
150 Composite
Strength (MPa)
100
Graphite
50
Toughness 0
MPa/m-1/2 0 0.2 0.4 0.6 0.8 1
Displacement (mm)
Steel >50
Monolithic Ceramic 3 Monolithic Composite
Platelet Reinforced Ceramic 6 Strength (MPa) Strength (MPa)
SiC 100 ± 50 220 ± 20
Chopped Fiber Reinforced 10
Continuous Fiber Reinforced 25-30 Graphite 107 ± 20 176 ± 20
Ceramic

7. Why Composites

8. Advantages:
Increased strength per unit volume
Lesser weight
Higher impact resistance
Greater through thickness strength

9. Ceramic Composites
Composite Examples

10. Structural Composites in Aerospace Applications
• Thermal protection system for a re-entry space vehicle:
Nose corn, leading edge, …
• Rocket engine: Extendable nozzle, aerospike engine, …
• Scram-jet engine for a future space vehicle.

11. Exhaust Tail-cone
Weaving / 2D Cloth + Stitching
Successfully engine demonstrated at gas temperature 1573K (1998)

12. SiC/SiC Thrust chamber
Weaving / 3-Axial Braiding
Successfully hot firing tested at gas temperature 2073K (1998)

13. Short History of Materials
10000 bc 5000 bc 0 1000 1500 1600 1900 1940 1960 1980 1990 2000
GOLD COPPER
BRONZE
IRON METALS
CAST IRON
POLYMERS/ STEELS ODS STEELS
ELASTOMER
WOOD
LIGHT ALLOYS NEW SUPERALLOYS
SKIN
FIBERS
GLUES SUPER ALLOYS GLASSY METALS
RUBBER TITANIUM,
COMPOSITES ZIRCONIUM
etc. ALLOYS HIGH TEMPERATURE
STRAW-BRICK HORSEHAIR
POLYMERS
PLASTER
STONE HIGH MODULUS
FLINT BAKELITE POLYMERS
POTTERY NYLON POLYESTERS CERAMIC
GLASS P.E. EPOXIES MATRIX
METAL
CEMENT PMMA ACRYLICS MATRIX
REFRACTORIES
CERAMICS/ PORTLAND C/C
GLASSES GFRE
CEMENT FUSED
SILICA PYROLITIC TOUGHENED
CERMETS CERAMICS CERAMICS
10000 bc 5000 bc 0 1000 1500 1600 1900 1940 1960 1980 1990 2000
Date

14. Yield Strength Strength of Various Materials
Yield of Various Structural Materials
600
500
Superalloy
C/C Composite
Ceramic Composites
400
Yield Strength (MPa)
SiC/SiC
300
Carbon Ste e l
Zircaloy
200
Stainle ss Ste e l
100
Graphite
0
0.0 400.0 800.0 1200.0 1600.0
Temperature (°C)

15. CERAMIC COMPOSITES
Latest and the most advanced material in
the market
Provide very high strength
Reduce weight greatly
Better impact properties
Higher in plane properties
Very high operating temperatures

16. CASE STUDY

17. Impact on 12mm steel plate
Muzzle Velocity=500m/s

18. Case Study: Ballistic Impact
Ceramic tiles are a good replacement for
steel armor plates
Weight Strength

19. Impact on ceramic tile
Muzzle velocity =1200m/s

20. Impact Characteristics
Monolithic ceramic tiles crumble under
impact loading
In plane properties are weak
Yet impact resistance is good because of
the failure mechanism of ceramic

21. Failure Mechanism
Under high energy impact ceramic
material fails, forming fine ceramic dust
This dust is confined by surrounding
ceramic structure
Thus it provides no route for failed
material to escape
As a result penetrating projectile faces
great resistance and loses out energy

22. Failure of monolithic ceramic
Muzzle velocity =1200m/s

23. Failure of monolithic ceramic
Muzzle velocity =1200m/s

24. Monolithic Ceramic: Problem
During the course of impact, layers of the
ceramic stacking move parallel to each
other due to inter-laminar shear stress
This causes delamination of the
monolithic crystal
Also monolithic crystal allows for easy
through thickness crack propagation

25. Effects of reinforcement
Reinforcement in the monolithic ceramic
tile improves ILSS properties
It prevents delamination to some extent
Through thickness crack propagation is
reduced
Reinforcing fibres take the impact loading
and prevent the matrix from cracking
Fibres help in holding the matrix together

26. SiC Whisker Reinforced Ceramic Tiles

27. Popular reinforcements
Glass fibre
Carbon fibre
Silicon carbide
Kevlar™

28. Popular Matrix Materials
Alumina
Zirconia
Zirconia toughened Alumina (ZTA)
Cr3C2
CeO2
TiN

29. Conclusion
Thus wherever weight constraints hinder
the use of thick steel plates, Ceramic
composites provide the best solution.
In defense applications ceramic
composite tiles are popularly used in
ballistic impact protection tiles and vests.
Ceramic composites are also popularly
used in high temperature applications
such as rocket nozzles and reactors.