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Basic definitions and concept about Materials along with its history
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MaterialsMaterials
Mushtaq 木塔西
ContentsContentsGeneral Material ClassificationsMetalCeramicPolymerReferences
Metal Metal Metals account for about two thirds of
all the elements and about 24% of the mass of the planet
The metal material offer higher modulus of elasticity, ductility, and resistance to elevated temperature. But, they are heavier and more difficult to process.
From the periodic table, it can be seen that a large number of the elements are classified as being a metal
Periodic Table of the Periodic Table of the ElementsElementsMetals Non-
MetalsCeramics(Ionic Bonds)
Metals(Metallic Bonds)
Polymers(Covalent Bonds)
Common Metallic Common Metallic MaterialsMaterialsIron/Steel - Steel alloys are used for
strength critical applicationsAluminum - they are easy to form,
readily available, inexpensive, and recyclable.
Copper – properties, including high electrical and thermal conductivity,
Titanium - Titanium alloys are used for strength in higher temperature (~1000° F)
common Metallic common Metallic Materials Materials Nickel - Nickel alloys are used for
still higher temperatures (~1500-2000° F) applications or when good corrosion resistance is required.
key feature of Metallic key feature of Metallic materialmaterialMetallic materials have free
electrons that are free to move easily from one atom to the next.
ExampleMetallic materials tend to be
good electrical conductors because the free electrons can move around within the metal so freely.
Ceramic Ceramic A ceramic has traditionally been
defined as “an inorganic, nonmetallic solid that is prepared from powdered materials, is fabricated into products through the application of heat.
CeramicCeramicCharacteristicsHigh strengthBrittlenessLight weightLow electrical conductivity
CeramicCeramicApplicationsStructural clay products (brick,
sewer pipe, roofing and wall tile, flue linings, etc.)
Glasses (flat glass (windows), container glass (bottles), pressed and blown glass (dinnerware), glass fibers (home insulation), and advanced/specialty glass (optical fibers))
Electrical (capacitors, insulators,,
magnets and superconductors)Chemical and environmental (filters,,
catalysts,)
PolymerPolymerYou may think of polymers as
being a relativelymodern invention!!!!!!!!!!!!!!!!!However naturally occurring
polymers have been used for thousands of years
Exampleswood, rubber, cotton, wool,
leather, silk,.. etc
PolymerPolymerArtificial polymers are, indeed,
relatively recentAnd mostly date from after WWIIIn many cases, the artificial
material is both better andCheaper than the natural
alternative
PolymerPolymerCharacteristicsLess dense than metals or ceramics,Resist atmospheric and other forms of corrosion,Offer good compatibility with human tissue, orExhibit excellent resistance to the conduction of electrical current.
PolymerPolymer Applications Styrofoam cups contact lenses rubber tires telephone housings sandwich bags soda bottles rubber bands computer keyboard keys. in fact, just look around your, house, dorm or apartment room and
you’ll likely find plenty of examples of polymeric materials.
Classification of PolymerClassification of PolymerTHERMOPLASTICS, THERMOSETS ELASTOMERS
Classification of PolymerClassification of PolymerTHERMOPLASTICSThe term ‘thermoplastic’ indicates that these materials melt on heating and may be processed by a variety of molding and extrusion techniques. polyethylene, polypropylene, polystyrene and polyvinyl chloride
Classification of PolymerClassification of PolymerThermo set ‘thermosetting’ polymers can not be melted or remelted.Examplesalkyds, amino and phenolic resins, epoxies, polyurethanes, and unsaturated polyesters.
Classification of PolymerClassification of PolymerElastomers Elastomers or rubbers can be elastically deformed a large amount when a force is applied to them and can return to their original shape (or almost) when the force is released
ReferencesReferenceshttp://www.ndt-ed.org/EducationResources/C
ommunityCollege/Materials/Introduction/introduction.htm
http://users.encs.concordia.ca/~woodadam/MECH221/Course_Notes/Polymers.pdf
THE CRC HANDBOOOK OF MECANICAL ENGINEERING BY JAMED. D Idol,RICHARD L.Lehmanhttp://www.amipp.rutgers.edu/assets/docum
ents/scholarlypubs/Polymers.pdf
Thanks for Thanks for patience!!!!!!!!!patience!!!!!!!!!