materials and wood

materials and wood

1. raw materials

   • are products extracted directly from nature
     • types
       • animal origin
       • plant origin
       • mineral origin

2. natural and processed materials

   • industrial processeds are applied to raw materials also known as natural resources, to turn them into processed materiald
     • classified in
       • artificial
       • synthetic

3. the propierties of materials

   • describe their qualites which determine their behaviour when subjected to external forces.

4. tools

   • the first tool made by humans
     • for many centuries humans used their hands as tools until their brains ability for abstract thought inspired them to use sticks and stones to make their actions more effective

5. wood

   • wood is the fibrous material that the trees are made of . it is made up of two main substances : cellulose and lignin
   • types
     • non-resinous
     • resinous
   • properties of wood
     • there are as many different types of wood as there are trees. this means that there is a wide variety to choose from
   • forms
     • strips
     • mouldings or profiles
     • boards and planks
     • beams
     • panels
     • sheets
   • working tools
     • cutting
     • machine
     • impact
     • assembly