Flashcards in Different Materials Deck (13):
What are Ceramics?
Hard, non metallic material such as brick or china
What are the typical properties of Ceramics?
High melting points
Hard and stiff but brittle
Poor conductors of heat and electricity
What is the make up of Ceramics?
Contain metals and non metals to form giant ionic lattices or giant covalent structures
How are most ceramics produced?
Heating clay to very high temperatures
Tiny crystals form joined together by glass
Can be coated in a glaze and reheated
What are the required properties for the material for an electrical cable?
Good conductor of electricity
What are the properties of Copper that make it a good or bad metal to use?
Good = best electrical conductor,
Bad = low tensile strength, high density (heavy)
Why is Aluminium chosen for overhead electricity cables?
Despite being not as strong as steel, it is a better conductor and is less dense
What are the 3 metal options for an electricity cable?
What are the required properties a material that is an insulator has?
Must prevent electric current passing through (poor conductor)
What are the 3 options of materials that could be used for an insulator?
What are the properties of Polypropene that make it a good or bad material to use?
Good = tough, flexible polmer
Bad = poorest electrical resistance, low tensile strength, low compressive strength
Why is Porcelain the material used for an insulator?
Medium electrical resistance, high compressive strength