10-04-2017, 08:16 PM
thermal engineering notes by nptel
Lecture Overview
What are composites ?
Importance and areas of application
Classification
Advantages of fiber reinforced composites
What are composites ?
Composite: Two or more chemically different constituents combined macroscopically to yield a useful material material.
Examples of naturally occurring composites
Wood: Cellulose Cellulose fibers bound by lignin matrix
Bone: Stiff mineral fibers in a soft organic matrix permeated permeated with holes filled with liquids liquids
Granite: Granular composite of quartz, feldspar, and mica
What are composites composites ?
Some examples of man made composites
Concrete: Particulate composite of agg g re ates (limestone or granite), sand, cement and water
Plywood: Plywood: Several Several layers of wood veneer glued together
Fiberglass: Fiberglass: Plastic Plastic matrix reinforced reinforced by glass fibers
Cemets: Ceramic and metal composites
Fibrous composites: Variety of fibers (glass, kevlar,
graphite, nylon, etc.) bound together by a polymeric matrix
These are not composites! composites!
Plastics: Even though they may have several fillers , their presence does not alter the physical properties significantly.
Alloys: Alloys: Here the alloy is not macroscopically macroscopically heterogeneous, especially in terms of physical properties.
Metals with impurities: impurities: The presence presence of impurities does not significantly alter physical properties of the metal.
Where are composites composites used?
Automotive industry: Lighter, stronger, wear resistance, rust free, aesthetics
Car body
Brake pads
Drive shafts
Fuel tanks
Hoods
Spoilers
Where are composites composites used?
Aerospace: Lighter, stronger, temperature resistance, smart structures, wear resistance Aircraft: Nose, doors, struts, trunnion, fairings,cowlings, cowlings, ailerons, ailerons, outboard outboard and inboard inboard flaps,stabilizers, elevators, rudders, fin tips, spoilers,edges
Rockets & missiles: Nose, body, pressure tanks,frame, fuel tanks, turbo motor stators stators, etc.
Satellites: Antennae, frames, structural parts
Where are composites composites used?
Sports: Lighter, stronger, toughness, better aesthetics, higher damp g in p p ro erties
Tennis
Bicycles
Badminton
Boats
Hockey
Golfing
Motorcycles
Where are composites composites used?
Transportation & Infrastructure: Lighter,stronger, toughness, damp g in
Railway coaches
Bridges
Ships and boats
Dams
Truck bodies and floors
RV bodies
Where are composites composites used?
And many more industry sectors
Biomedical industry
Consumer goods
Agricultural equipment
Heavy machinery
Computers
Healthcare