Engineering - Materials Flashcards
What are the 3 main steels?
Low carbon (mild)
High carbon
Stainless
What is a ferrous metal?
A metal that contains iron and is magnetic
What is the difference between low carbon and high carbon steel?
Low carbon steel is a carbon-iron alloy with a low percentage of carbon making it softer
High carbon steel has more carbon so it is harder
What is stainless steel?
An alloy of iron, carbon along with nickel and chromium so that it doesn’t rust
What is iron and what is it used for?
A magnetic, soft metal that rusts easily meaning that it is usually alloyed with carbon to make steel which is harder and still magnetic
It is used for machinery, cars, ship hills and components of buildings
What is aluminium and what is it used for?
A very common, non-magnetic metal that is very durable and lightweight and can be alloyed to make it harder
It is used for buildings, vehicles and some household items and devices
What is copper and what is it used for?
Red colour, extremely conductive, non-magnetic, ductile (can be pulled into white) metal which is used for electrical wiring and some colourings
What is brass and what is it used for?
A metal alloy made from copper and zinc and it is cheap and shiny meaning it is used decoratively
What is a thermosetting plastic?
Once set, these plastics can’t be reheated to soften and re-shape because the molecules are linked in 3 dimensions
What is epoxy resin?
It is an adhesive that sets in order to hold 2 materials together (can bond wood, some metals and some plastics)
What is urea formaldehyde and what is it used for?
A thermosetting plastic that is hard and strong and is also a good electrical conductor so it is used for electrical fittings
It is also scratch resistant
What are polyester resins and what are they used for?
When a resin is combined with fibre glass and some other materials, a polyester resin is formed that is a very tough material that can resist impact
It is used for car body repairs, sailing boats, corrugated sheet because of its lightness and resistance to water
What is acrylic?
It can be translucent, transparent or opaque and is resistant to acids and most weather conditions but it can snap fairly easily if used as a thin sheet
What is a thermoplastic?
A plastic that can be re-heated and shaped again into a different shape meaning it is good for recycling
It can do this because the hotter the temperature, the weaker the bonds between molecules
What is PVC and what is it used for?
A tough material that can be flexible or hard. It can also be bonded with adhesives
It is used for water pipes, coatings for wires and raincoats since it is strong and waterproof
What is polyethylene and what is it used for?
The most commonly used plastic in everyday life, it is cheap to make but has a low melting temperature
It is used for plastic bottles, plastic bags abs children’s toys because of its cost
What is nylon and what is it used for?
It’s oily means that low friction is caused so it is used in gears, bearings, wheels and some clothing
What is ABS and what is it used for?
A very tough, scratch-resistant, chemical-resistant plastic that is used for casings for many appliances
What is a composite?
Materials made from 2 or more materials for added strength, toughness or hardness
What are the 4 main composite types?
Composite building materials
Reinforced plastics
Metal composites
Ceramic composites
What are composites used for?
Buildings
Bridges
Structures
A few other things
What are the 3 advantages of composite materials?
Lightweight
High strength to weight ratio
Can be moulded / laid-up into complex shapes
What are the 3 disadvantages of composite materials?
Time consuming to manufacture
Expensive
Cannot be recycled
What are the 7 terms you use to describe materials?
Ductile (ability of material to be pulled out)
Tough (be able to withstand sudden impact without fracture)
Malleable (ability to withstand deformation by compression)
Hardness (resists abrasive wear, indentation or deformation)
Strong (withstand force without breaking or permanently bending)
Tensile (won’t easily break or snap)
Corrosion resistant (weather resistant and no rust)
What are the 2 composite materials?
Glass reinforced plastic
Carbon fibre
Properties of glass reinforced plastic
Good strength to weight ratio, easily moulded and shaped, corrosion resistant and quite inexpensive
Properties of carbon fibre
Good strength to weight ratio, easily moulded and shaped, corrosion resistant and expensive
What is a smart material?
A material that can change one or more of its properties because of a change of its conditions
What are the 2 smart materials?
Shape memory alloy
Shape memory polymer
Properties of shape memory alloys
Return to original shape when heat is applied
Lightweight and expensive
Properties of shape memory polymers
Same as alloys but lightweight and corrosion resistant
What are the 3 properties of ceramics?
Heat resistance
Strong
Hard
