Materials Materials and Components

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MaterialsMaterials and Components

• To choose the correct material for any particular
  task is essential for a manufacturing activity.
• Materials are divided into natural and artificial
• Natural resources are split into 3 categories
• Animal
• Vegetable
• Mineral
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Materials

• Artificial Materials .
• ARE THOSE WHICH HAVE BEEN MADE BY MAN

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Materials

• TYPES OF MATERIALS
• 1º Wood Divided into two major classifications
• Hardwoods and Softwoods
• 2º Metals. There are two significant groups of
  metals
• Ferrous metal contain iron
• Non-ferrous metals do not contain iron

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Materials

• .
• Ferrous metal example

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Materials

• Non-Ferrous metals
• Examples of Non-ferrous metals are
• Aluminium
• Copper
• Gold
• Silver

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MaterialsPlastic

• Made using coal, gas, animal protein or petrol
• On the left, Coal and plastic bottles

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MaterialsCeramic, Textiles and Glass

• Other Materials used in manufacturing activity
  are Ceramic, textiles and glass

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MaterialsProperties of Materials

• Properties of materials can be divided into
  physical,chemical and ecological

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MaterialsPhysical Properties

• Electrical Conductivity
• When electricity can run though the material.
• Examples
• Steel is a good conductor
• Wood isn't a good conductor

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MaterialsPhysical Properties

• Optical properties
• How materials behave when light touches them
• Them can be classified into
• a) Opaque No light travels through them. e.g
  wood
• b) Transparent All light travels through them
  and you can see what's behind the materials. e.g
  glass of window
• c) Translucent All light can travel through them
  but you cannot see what's behind them e.g frosted
  glass
• See examples on page 75

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MaterialsThermal Conductivity

• What is conductor and what is insulator ?
• Plastic handles..
• Metal Body.

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MaterialsThermal Conductivity

• . The ability of the material to conduct heat.
  e.g. Saucepan. Metal body for thermal
  conductivity and plastic handles for thermal
  insulation.
• Thermal Insulation It is a bad Thermal
  conductor

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MaterialsThermal properties

• . Dilation
• When material expands ( gets bigger ) due to heat
  
• Contraction
• When material gets smaller due to heat
• To think about Why are rails separated by a
  gap?

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MaterialsThermal properties

• . Fusibility is the ability of a material to
  change into a liquid when heated to its melting
  point.
• examples of melting points
• Irons melting point...........1535 ºC
• Coppers melting point..........1083 ºC

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MaterialsSound Properties

• The ability of materials to conduct sound
• To think about. Can you speak on the moon?
• Write some examples of good and bad conductors.

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MaterialsChemical Properties

• Oxidation.
• The change that occurs to most metals when in
  contact with air or/and water

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Materials Ecological Properties.

• Recyclable. Materials that can be reused
• Toxic. Materials which are harmful to the
  environment
• Biodegradable. Materials that decompose naturally
  with time. eg
• An apple take about 20 days to decompose
• Plastic takes about 100 years
• Glass takes about 400 years

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Materials

• Now, visit this web site
• bbc.co.uh

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Materials

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Materials

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Materials

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