This document discusses different types of ceramics and their applications. It describes traditional ceramics like bricks, tiles and pottery as well as engineering ceramics used in tools, bearings, and electronics due to their high strength, hardness, and heat and corrosion resistance. Specific ceramics discussed include alumina, silicon carbide, silicon nitride, partially stabilized zirconia, and sialons. Their properties and uses in applications like engines, furnaces, and cutting tools are outlined. The document also summarizes particle-reinforced and fiber-reinforced composites, describing how particles or fibers improve metal matrix strength for aerospace and cutting tool applications.
7. Characteristics of ceramics
• Used in high temperature places
• Its strong, hard and brittle
• High melting point
• Good thermal and electrical insulators
• Resistant to oxidation and corrosion
• Having high compressive strength but are weak intension
8. Engineering ceramics
• Its specially for engineering applications
• They are basically oxides, carbides, sulphides
and nitrides of metal.
9. Characteristics of engineering ceramics
• High resistance to abrasion and wear
• High strength at high temperature
• Good chemical stability
• Good electrical insulation characteristics.
13. Properties of Alumina
• Excellent hardness, wear resistance
• They are more stiffer than steel
• More stronger in compression than hardened steel
• Very good environmental resistance (CORROSION)
• Alumina mixed with ceramics to get high tensile
and toughness properties.
14. Applications of alumina
Used in
• Spark plug insulators
• Electronic circuits
• Rocket nozzles
• Electrical and electronics devices
• In nuclear power plant
• bearings
16. Properties of Sic
• High tensile strength
• High stiffness , hardness
• Better dimensional stability
• Good wear resistant
• Good corrosion resistant.
17. Applications of Sic
Used
• As a abrasives for grinding wheel
• As a coating material
• As a refractory tubes
• In nuclear reactor
• In bearings
• And in very high temperature places
19. Properties of silicon nitrides
• Resistant to strong acids
• Resistance to thermal
• Low density and low weight
• Low thermal expansion
• More stiffer
20. Applications of silicon nitrides
Used in
• Cutting tool materials
• Turbine parts
• Pump parts
• High temperature engineering components
21. Partially stabilized zirconia (PSZ)
• It’s a zirconium oxide
• Blended and sintered with others like
magnesium oxide, calcium oxide
29. COMPOSITES
• Two or more materials added to get require qualities in
a material.
• The weakness of one metal rectified by the strength of
second metal
• Example
Aerospace components
• That should have low weight , stiffness, impact and
corrosion resistance, good abrasive properties.
31. Particle re-inforced (FIBER)
composites
• Its consist of particles of one material dispersed in a matrix of
a second material
• The fine dispersion particle posses
good strength in composites.
• The size, distribution and orientation of particles defines the
strength of the composite.
• Types
1. dispersion strengthened composites
2. Large particle composites
33. 1.Dispersion strengthened composites
• The particles are smaller and having diameter 0.01 –
0.1 microns and volume concentration 1 – 15 % of fiber
• This method is similar to that for precipitation hardening.
• Due to this , the composites have good yield and
tensile strength. And the plastic deformation is
restricted.
34. 2. Large particle composites
• The particles diameter greater than 1 micrometer and volume
concentration are greater than 25 %
• Here the load on this composite is shared by both matrix and
particles.
• It posses good strength
• Tungsten carbide or Titanium carbide embedded in a metal
matrix of cobalt or nickel.
• These composites used as a cutting tool
35. FIBRE REINFORCED COMPOSITES
• Here the dispersed phase is in the form of fibers.
• These fibre reinforced composites having improved
strength, fatigue resistant, stiffness and strength-to-
weight ratio
40. Advantages
• Good mechanical properties – high toughness, elastic
modulus, good fatigue properties
• Used in light weight needed places
• We can fabricate to any shape and size
• Good aero- space applications than conventional
materials.
• Good corrosion resistance
• Not much sensitive to thermal shocks and
temperature changes.
41. Limitations
• High cost than many conventional materials
• Polymeric materials cannot be used for high
temperature applications.