materials and components Flashcards
natural materials
deirved from plants, animals or ore
e.g wood, wool
composite materials
two or more materials bonded or combined together to improve properties
e.g plastics
synthetic materials
man made via scientific processes
e.g carbon fibre, nylon, kevlar
smart material
react to environment when introduced to stimuli
e.g thermochromic ink, photochromic glass
regenerated material
re used or processed into different material
alloys
mixture of elements where one is metal
e.g steel, brass etc
polymer
synthetic (designed by chemical engineers) to meet customer demands, fall into two categories: thermosetting plastic or thermoplastic
thermoplastics
can be reshaped by heating
which plastics are thermoplastics?
-PET
-PVC
-PP
-HDPE
-LDPE
-ABS
-Acrylic
-Nylon
-HIPS
thermosetting plastics
cannot be reshaped by heating so can withstand higher temperatures
which plastics are thermosetting plastics?
-polyester resin
-epoxy resin
-urea formaldehyde
conductivity
conduct heat or electricity
strength
withstand impact or force without deforming or breaking
elasticity
bend or deform and return to original shape
plasticity
permanently change form or shape
malleability
material deformed or bent in all directions without breaking
ductility
stretch without breaking
hardness
withstand scratches, indentation and wear
toughness
withstand sudden impact or blows without breaking
durability
withstand constant wear
wool properties
good thermal qualities and resistance to fire
copper properties
-non ferrous metal
-melting point of 1100 degrees
-good electrical and heat conductivity
-good resistance to corrosion
-ductile
-malleable
copper uses
electrical wire, saucepans and copper water pipe
how is plywood made
layers of hardwood veneer bonded together with the grain direction in each layer laid at a 90 degrees to the previous layer
red cedar properties
-softwood
-resistance to rotting
-expensive
red cedar uses
outdoor e.g shed
oak wood properties
-hardwood
-tough and durable
-resistant to rot and damp environment
oak wood uses
-high quality furniture
-flooring
-fences
chipboard properties
-used when appearance and strength are less important than cost
-prone to expansion and discolouration
chipboard uses
-ikea furniture
carbon fibre properties
-high strength to weight ratio
-high tensile strength
carbon fibre uses
-racing car shells
Glass reinforced plastic (GRP) properties
-high strength to weight ratio
-durable
-weather resistant
Glass reinforced plastic (GRP) uses
-surgical casts
-garden products
-outdoor play equipment
kevlar properties
-impact resistant
-high strength to weight ratio
-durable
kevlar uses
-protective equipment and body armour
-phone cases
nylon properties
-tough and durable
-food safe
-resistant to wear
nylon uses
-kitchen utensils
-guitar strings
-dog togs
-gears
acrylic properties
-many colours
-resistant to chemicals
-brittle on impact much less likely to break then glass
-thermoplastic so can be moulded with heat
acrylic uses
-lenses
-car headlamp covers
melamine formaldehyde properties
-heat resistant
-non-toxic
-hard and rigid
-excellent surface finish
melamine formaldehyde uses
-dishes
epoxy resin properties
-thermosetting polymer
-electrical and heat insulation properties
epoxy resin uses
-white powder coatings
-adhesives
PET properties
-moderate chemical resistance
-transparent
PET uses
-bottles
-food containers
PC properties
-transparent
-tough
PC uses
-used as a safer alternative for glass
-1st gen iMac
-protective glasses
HDPE properties
-strong and stiff
-excellent chemical resistance
-excellent finish
HDPE uses
-bowls
-buckets
-pipes
PVC properties
-good chemical and weather resistance
-tough and stiff
-lightweight
PVC uses
-pipes
-guttering
-window frames
-bottles
LDPE properties
-tough
-flexible
-good chemical resistance
LDPE uses
-toys
-transparent packaging
-carrier bags
PP properties
-lightweight
-food safe
-excellent chemical resistance
-good electrical insulator
PP uses
-food containers
-rope
HIPS properties
-stiff
-good impact resistance
-scratch resistant
HIPS uses
-toys
-refrigerator linings
ABS properties
-tough and durable
-rigid and stiff
-high impact resistance
ABS uses
-Lego
-many household items (e.g telephone, kettle)
thermochromic ink
changes colour depending on the temperature
thermochromatic material properties
change colour in different temperatures
thermochromatic material uses
smart colour pigments in plastics e.g kettle, baby bottle, mug etc
photochromic glass
changes colour when subjected to light e.g lenses on expensive sunglasses that darken in the light
what is the difference between ferrous and non ferrous metals
if the metal is iron or contains it it’s ferrous, all other are non-ferrous
examples of ferrous metals
-steel
-stainless steel
-cast iron
examples of non-ferrous metals
-aluminium
-copper
-brass
properties of ferrous metals
-magnetic
-rusts
-durable
cast iron properties
-strong but brittle
-resistant to rust
-easily cut into shapes
cast iron uses
saucepans
non-ferrous metal properties
-don’t contain iron (will not rust)
-non magnetic
zinc properties
-resistant to corrosion
-brittle
-recyclable
zinc uses
-coatings
-rubbish bins
low carbon mild steel properties
-tough and durable
-shaped and cut
-will rust
low carbon mild steel uses
-car bodies
-nails
-frames
high carbon steel properties
harder then low carbon mild steel
high carbon steel uses
-tools
-blades
stainless steel properties
-tough
-hard to cut
-good resistance to corrosion
stainless steel uses
-cutlery
-saucepans
-sinks
what factors must be considered before carrying out the finishing product
function, protection and aesthetics
what is anodising
electrical process of giving aluminium a decorative coloured coating
what is galvanising
mild steel dipped in hot molten zinc for a coating
how does galvanising protect the material
mild steel rusts when exposed to water but zinc does not
why are varnish, teak oil and wax used
to enhance the grain to make product look better and to protect against the weather
what is plastic coating
mild Steel heated and dipped in polythene powder
gives good protection and has many colours
how does powder coating work
electrically charged plastic powder that sticks to the metal
then the metal is placed in a kiln so that the plastic coating cures and sticks to the metal
what are examples of permanent joints
-welding and soldering
-brazing
-adhesive
what are examples of temporary joints
-nuts and bolts
-screws
-clips
-brackets
-knock-down fittings
knock down fittings
-put together using a screwdriver
-temporary
-used for flatpacks
advantages of use of knockdown fittings in flatpack furniture
+cheaper- manufacture doesn’t have to pay anyone to assemble
+less space to store in warehouse
+transport costs lower
disadvantages of use of knockdown fittings in flatpack furniture
-can be difficult to assemble
-quality can be poor
