Metals and Processes Theory'

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METAL
Metals and Processes Theory. Knowledge and
Understanding.
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Metal Theory.
Metals can be divided into THREE main categories
FERROUS, NON FERROUS AND ALLOYS.
Ferrous metals Facts.
Ferrous metals contain iron this means they are
magnetic and they rust. Fe is the chemical symbol
for iron. Examples Cast iron, Mild steel, Medium
carbon steel, Stainless steel, and High speed
steel.  
Non Ferrous metals Facts.

• Non-ferrous metals do not contain iron, they do
  not rust and they are
• not magnetic.
• Examples Aluminium, Duralumin, Copper, Zinc,
  Brass, Gold, Silver and Tin.

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Metal Theory.
Alloy Facts.

• An alloy is a mixture of two or more elements, at
  least one of which is a metal.
• Alloying one metal with others often enhances its
  properties
• Steel is the most common alloy (iron and carbon)

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Metal Theory.
FERROUS
Stainless Steel - Hard and tough, resists wear ,
heavier than aluminium and it does not rust.
There are different grades and surface finishes
of stainless steel to suit the environment to
which the material will be subjected in its
lifetime. Common uses of stainless steel are
cutlery and watch straps, and outdoor furniture.  
NON FERROUS
Aluminium Good strength, light, soft, easy to
bend, doesnt rust, good conductor of heat and
electricity. Generally used in Kitchen equipment,
window frames, general cast components.  
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Metal Theory.
1. Metal is divided into two groups, they are
METAL
Ferrous
Non - Ferrous
2. Briefly describe the difference between them
Ferrous metals contain iron this means they are
magnetic and they rust. Fe is the chemical symbol
for iron.  
Non-ferrous metals do not contain iron, they do
not rust and they are not magnetic.
3. What is an alloy?
Metals mixed together to make new metals with
different properties, are called alloys.    
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Metal Theory.
4. Name and briefly describe two methods of
shaping metal  
Casting
What is it?
Casting is a metal-forming process.  Molten metal
is poured into a mould, when cooled it solidifies
and takes on the characteristic shape of the
mould.  
Where are they used.
Casting is used to produce intricate shapes in
metal and is used for mass production. Such as
car engines and workshop vices.  
Products made
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Metal Theory.
Extrusion
What is it?
The principle of this process is very similar to
squeezing toothpaste from a tube. Extrusion is a
manufacturing process used to create long objects
of a fixed cross-sectional profile.
How is it done?
A material, often in the form of a billet, is
pushed through a die of the desired profile
shape. Extrusion may be continuous (producing
indefinitely long material) or semi-continuous
(producing many short pieces).