Properties of Materials Mechanical Properties, Chemical Properties, Physical properties , General Properties of materials,

1. Get the box of StuffGet the box of Stuff
Wood, steel, aluminum, melamineWood, steel, aluminum, melamine

2. Properties of MaterialsProperties of Materials
Goal: Students will be able toGoal: Students will be able to
describe various physicaldescribe various physical
properties that materials haveproperties that materials have

3. DiscussionDiscussion
 differentiate between chemical anddifferentiate between chemical and
physical propertiesphysical properties
 At your tables list examples of chemicalAt your tables list examples of chemical
and physical properties.and physical properties.
 I will call on each table and make a list ofI will call on each table and make a list of
all the ones we can think of.all the ones we can think of.

4. Chemical PropertiesChemical Properties
 how a material interacts with anotherhow a material interacts with another
materialmaterial
 ““social” behaviorsocial” behavior
 response to other matter (or lack ofresponse to other matter (or lack of
response)response)
 reactionsreactions

5. Chemical PropertiesChemical Properties
 Examples:Examples:
 burningburning
 reaction with acidreaction with acid
 reaction with waterreaction with water
 corrosion/rusting/oxidationcorrosion/rusting/oxidation
 others????others????

6. Physical PropertiesPhysical Properties
 characteristics it possesses by itselfcharacteristics it possesses by itself
(in and of itself)(in and of itself)
 ““personal” traitspersonal” traits
 response to energyresponse to energy

7. Physical PropertiesPhysical Properties
 colorcolor
 sizesize
 texturetexture
 melting pointmelting point
 boiling pointboiling point
 solubilitysolubility
 lusterluster
 densitydensity
 magnetismmagnetism
 odorodor
 viscosityviscosity
 crystalline structurecrystalline structure

8. Physical PropertiesPhysical Properties
 ElectricalElectrical propertiesproperties
 conductor or insulatorconductor or insulator
 OpticalOptical properties – response to lightproperties – response to light
 index ofindex of refractionrefraction – bending of light– bending of light
 transparenttransparent – light passes through– light passes through
 translucenttranslucent – some light passes through but no– some light passes through but no
distinct imagedistinct image
 opaqueopaque – no light passes through– no light passes through

10. Physical PropertiesPhysical Properties
 ThermalThermal properties – response to heatproperties – response to heat
 conductivityconductivity
 specific heat – how much energy it takes tospecific heat – how much energy it takes to
change temperaturechange temperature
 thermal expansion –thermal expansion – example: iron wireexample: iron wire
demodemo

11. Mechanical PropertiesMechanical Properties
 subgroup of physicalsubgroup of physical
 response to force or stressresponse to force or stress
 forceforce – a push or pull– a push or pull
 stressstress – force causing a deformation or– force causing a deformation or
distortion (force per unit area)distortion (force per unit area)

12. Mechanical PropertiesMechanical Properties
ExamplesExamples
 workabilityworkability
 malleabilitymalleability – can be flattened– can be flattened
 ductilityductility – can be drawn into wire– can be drawn into wire
(stretched), bent, or extruded(stretched), bent, or extruded

13. Mechanical PropertiesMechanical Properties
ExamplesExamples
 brittlenessbrittleness
 breaks instead of deforming when stress isbreaks instead of deforming when stress is
appliedapplied
 hardnesshardness
 resistance to denting or scratchingresistance to denting or scratching

14. Mechanical PropertiesMechanical Properties
ExamplesExamples
 elasticityelasticity
 ability to return to original shape afterability to return to original shape after
being deformed by stressbeing deformed by stress
 rubber ball or piece of elasticrubber ball or piece of elastic
 plasticityplasticity
 retains new shape after being deformed byretains new shape after being deformed by
stressstress
 wet clay ball or piece of saran wrapwet clay ball or piece of saran wrap

15. Some of the propertiesSome of the properties
 At your tables you will find some signsAt your tables you will find some signs
with different physical properties.with different physical properties.
 Go around between tables and answer theGo around between tables and answer the
questions on a separate piece of paper.questions on a separate piece of paper.

16. Index of Refraction
Question. What two materials here have a similar index of refraction?
(the three materials are glass, HDPE, and mineral oil)
Electrical conductivity
What materials here are non-conductive electrically?
(the materials are brass, copper coated steel, wax, glass and carbon fiber)
Hardness
Which material here is the hardest?
(Pine and Melamine)

18. Mechanical PropertiesMechanical Properties
ExamplesExamples
 toughnesstoughness
 ability to absorb energyability to absorb energy
 resistance to fractureresistance to fracture
 strengthstrength
 resistance to distortion by stress or forceresistance to distortion by stress or force
 several types: tensile, compressive,several types: tensile, compressive,
torsional, bending, sheartorsional, bending, shear

19. Types of Stresses/ForcesTypes of Stresses/Forces
 TensionTension
 pullingpulling

examples:examples: tug-of-war, slingshottug-of-war, slingshot
 CompressionCompression
 pushing together or squeezingpushing together or squeezing

examples:examples: bed springs, can crusher, bench visebed springs, can crusher, bench vise

21. stress
strain
Ceramic or
glass
metal
polymer
straight line = elastic region
curved line = plastic region

22. City of MaterialsCity of Materials
 http://www.cityofmaterials.comhttp://www.cityofmaterials.com

27. General Classes of MaterialsGeneral Classes of Materials

28. PolymersPolymers

29. CeramicsCeramics

30. CompositesComposites

31. Metals and AlloysMetals and Alloys

32. Metals and AlloysMetals and Alloys

33. Wood and Wood ProductsWood and Wood Products

34. Free writeFree write
 On a piece of paper please describeOn a piece of paper please describe
various physical and chemical propertiesvarious physical and chemical properties
that material's have. If you can includethat material's have. If you can include
how you could test those physicalhow you could test those physical
properties.properties.