what is toughness defined as?
the level of resistance to crack propagation
what are some general facts/properties of metals?
- strong
- ductile
- high thermal and electrical conductivity
- opaque and reflective
what are ceramics compounds of?
they are compounds of metallic and non-metallic elements - oxides, carbides, nitrides and sulphides
what are some general facts/properties of ceramics?
- brittle
- glassy
- elastic
- non conducting
what are some general facts/properties of polymers?
- covalent bonded
- soft
- ductile
- low strength & density
- thermal and electrical insulators
- optically translucent or transparent
what size range are we looking at when talking about macro properties?
centimetres (1cm = 10^-2m)
what size range are we looking at when talking about macro structure?
milimetres (1mm = 10^-3m)
what size range are we looking at when talking about micro structure?
micrometres (1μm = 10^-6m)
what size range are we looking at when talking about molecular structure?
nanometres (1nm = 10^-9m)
what size range are we looking at when talking about atomic structure?
angstrom (0.1nm = 10^-10m)
what is an allotrope?
each of two or more different physical forms in which an element can exist. Graphite, graphene, charcoal, fullerene and diamond are all allotropes of carbon
what is graphene?
carbon nanotubes rolled up
what is the hardest material known to man?
diamond
