UNIT 2

UNIT 2

1. Raw materials

   • extracted from nature
   • origin
     • plant
     • animal
     • mineral

2. Natural and processed materials

   • natural materials
     • industrial processes
       • processed materials
         • artificial
           • from nature
         • synthetic
           • from humans

3. The properties of materials

   • mechanical
     • hardness
     • mechanical resistance
     • toughness
     • brittleness
     • elasticity
     • plasticity
   • thermal
     • expansion
     • thermal conductivity
   • environmental
     • toxicity
     • environmental hazard
     • recyclability
     • biodegradability

4. Tools

   • carry mechanical work and tasks
   • first ones
     • hands
     • stones and sticks
     • carved stones
   • types
     • assembly
     • marking
     • measurements
     • impact
     • cutting and levelling
     • support

5. Wood and types of wood

   • made of
     • cellulose
     • lignin
   • parts of trunk
     • heartwood
     • pith
     • bark
     • cambium
     • growth rings
     • sapwood
   • types
     • non-resinous
     • resinous

6. Properties of wood

   • hardness
   • thermal and electrical insulation
   • flexibility
   • density
   • hygroscopicity
   • splitability
   • sound conductivity
   • toughness

7. Forms of wood

   • natural
     • strips
     • mouldings
     • boards
     • beams
     • panels
     • sheets
   • prefabricated
     • uniform
     • doesn't warp
     • finishes
     • damp-proofing
     • good for sawing
     • standard sizes
     • cheaper
   • commercial
     • plywood
     • chipboard
     • fibreboand

8. Wood working tools

   • cutting
     • hand saw
     • hacksaw
     • machine
   • impact
     • hammers
     • spanners
   • assembly
     • spanners
     • screwdrivers
   • shaving and drilling
     • planning and levelling
     • boring
     • machine

Imagens e arquivos do mapa