Material properties

• what are the 3 categories of materials

  • traditional
  • modern
  • smart
• definition of traditional materials

  materials that have been used for many centuries
• definition of modern materials


  materials developed in the last century
• definition of smart materials

  materials that change physical properties
• material classifications (hint 6)

  • metals
  • timber/wood
  • polymers
  • paper and board
  • composites
  • smart and modern materials
• property of metas

  made up of crystals that contain atoms and molecules
• property of woods


  fibrous materials made up of plant cells and resins
• property of paper and boards

  derived from wood so share the same molecular structure
• property of polymers


  made up of long chain molecules containing carbon, hydrogen and oxygen atoms along with other chemicals such as chlorine and fluorine
• what are the physical properties (hint 11)

  • fusibility
  • density
  • electrical conductivity
  • electrical insulation
  • semi-conductors
  • thermal properties
  • opacity
  • transparency
  • translucency
  • colour
  • surface
• fusibility is

  the ability to change into a molten or liquid state when heated to a certain temperature
• density is

  defined as mass per unit volume - relative density is the ratio of the density of the substance to that of pure water at 4 degrees C
• electrical conductivity is

  offer low resistance to the flow of electrical current
• electrical insulation is

  offer a high resistance to the flow of electricity
• semi-conductors are

  allowing electric current flow under certain conditions
• thermal properties are

  how a material reacts to heat - expansion, conductivity and insulation
• opacity is

  how much light can pass through
• transparency is

  the ability for light to fully pass through
• translucency is

  the ability for light to transmit through when not being able to see through
• colour is

  light bouncing off a surface of a material - classed as an optical property
• surface is

  how light bounces off a material to give an indication of how smooth or rough the surface of the material is
• what are the mechanical properties

  • plasticity
  • malleability
  • ductility
  • elasticity
  • toughness
  • hardness
  • durability
  • stability
  • strength
• plasticity is


  the ability of a material to be permanently changed in shape by an external force without damage
• malleability is


  the ability to withstand deformation by compression
• ductility is


  the ability to be drawn out
• elasticity is


  the ability to flex and return to its normal shape when the force is removed
• toughness is


  the ability to withstand a sudden impact - can also withstand bending
• hardness is


  the ability to withstand abrasive wear
• durability is


  the ability of a material to withstand wear and tear as well as weathering and corrosion
• stability is


  the ability to resist changes in the shape and size due to its environment
• strength is


  the ability to withstand forces without breaking of being permanently deformed
• what are the different types of strength

  • tensile strength
  • compressive strength
  • bending strength
  • shear strength
  • torsional strength
• tensile strength is


  the ability to withstand stretching or pulling forces

  
• comprehensive strength is 


  the ability to withstand pushing or crushing forces

  
• bending strength is


  the ability to withstand forces which attempt to bend the material

  
• shear strength is


  the ability to withstand sliding forces acting against each other

  
• torsional strength is


  the ability to withstand twisting forces