Materials and Properties Flashcards
What are two advantages of using MDF over natural timber?
MDF is cheaper and has a smooth uniform surface, making it easier to machine and finish.
What is a thermoplastic, and how does it differ from thermosetting plastic?
A thermoplastic can be reheated and reshaped, whereas a thermosetting plastic sets permanently after being heated once.
Properties of plywood.
Strong due to cross-grain construction, resistant to cracking, warping and shrinking.
What is a disadvantage of using natural timber?
It can be prone to warping or splitting if not treated properly or maintained.
What is the main difference between ferrous and non-ferrous metals?
Ferrous metals contain iron, will rust and react to a magnet while non-ferrous metals do not.
What is an example of a non-ferrous metal?
Aluminium - lightweight, corrosion-resistant and has good conductivity.
Advantage of using copper.
Excellent conductivity and corrosion resistance.
Disadvantage of using aluminum.
While it is lightweight, it is not as strong as steel and can be prone to scratching.
Examples of non-ferrous metals that wont rust or react to a magnet
Aluminium, brass and copper
Examples of ferrous metals that would rust and react to a magnet
Cast Iron
Mild Steel
High speed steel
Stainless steel
Softwood examples
Pine
Spruce
Cedar
Larch
Hardwood examples
Oak
Beech
Mahogany
Ash
Examples of manufactured boards
Plywood
Chipboard
Hardboard
MDF
Properties of ABS
Durable
Chemical resistant
Good impact resistance
Scratch resistance
Properties of polypropylene
Chemical resistant
Wide range of colours
Durable
Lightweight
Name other methods, other than wood joints that can be used to join wood.
Nails
Screws
Glue
Knock down fittings
Disadvantage of welding as a method of joining metal
Does not leave a neat finish when the weld metal is melted at the joint of the two metal pieces
What is a self-tapping screw?
It is a screw that cuts its own thread into a pre-drilled hole in METAL
Purpose of a metal tap
A tap cuts an internal thread in a pre-drilled hole in metal
Purpose of metal die
A die cuts an internal thread on metal rod
