C10 Flashcards
What are ceramics?
Ceramics-> non-metals with high melting points that arn’t made of Carbon-based compounds
- Clay
- Clay is soft when dug up= molding into diff shapes
- Hardens when fired
- This makes it ideal for pottery + bricks
How is glass made what is it an example of?
- Example of a ceramic
- Glass is genrally transparent but can be moulded when hot can be brittle when thin
- Mode glass is made from Soda-lime glass made from a mixture of limestone, sand and sodium carbonate (soda) unill it melts. Mixture cools=>glass
- Borosilicate glass higher melting point. Made in same way using mixtur of sand + bron trioxide
What is a composite?
Composites-> Made of one material embedded in anouther. Fibers of a material (reinforcements) surrounded by a matrix acting as a binder.
Properties vary depending on the properties of the material it’s made of.
What are diffrent examples of composites?
- Fibereglass
2.Carbon fibre
3.Concrete - Wood
Fibreglass
- Fibers of lass embedded in a matrix of polymer (plastic)
- Low density (like plastic) but very strong (like glass)
- Uses: Skis, boats and surfboards
Carbon fiber
- Polymer matrix.
- Renforments eather long chains of carbon atoms bonded togther (Carbon fibers) or carbon nanotubes
- Very strong and light
- Uses: Aerospace and sport car manufacturing
Concret
- Made from aggregate (mixture of sand + gravel) embedded in cement
- Very strong
- Ideal for use as a building material e.g.skate parks
Wood
Natural composite of cellulose fibers held toghether by an organic polymer matrix
What makes/determins the properties of polymers?
reactton conditions ( temp + pressure)
What are the 2 types of poly(ethene)
- Low density (LD)-> is made from ethene at a moderate temp under high pressure with catalyst. It’s flexable and is used for bags and bottles
- High density (HD) poly(ethene) is also made from ethen but lower temp and pressure with diff catalyst. More rigid and is used for water tanks and drainpipes
The ………… that a polmer is made from determins the type of ………… that form bewtween the polymer ……… theses ……… bonds between the diff molecule chains determine the properties of the polymer
The monomers that a polmer is made from determins the type of bonds that form bewtween the polymer chains .Theses weak bonds between the diff molecule chains determine the properties of the polymer
What are the 2 diffrent types of polymers?
Thermosoftening-> contain individual polymer chains entwined together with weak forces between the chains. You can melt these plastics and remould them.
Thermosetting polymers->Contain monomers that can form cross-links between the polymer chains holding the chains thogether in a together solid structure. Don’t soften when heated. They are strong , hard and rigid
What are the uses and properties of ceramics?
Procelain
Bricks
Insulators of heat + electricity
brittle (arn’t flexable + break easly)
Stiff
What are the uses and properties of composites?
dependant on the matrix/binder and renforcement
What is steel?
- Alloy of iron
- added small amounts of carbon and other metals
