DT: materials

?
what are the properties of smart materials?
Often react to the environmental conditions such as heat, light and movement
1 of 42
what does the term mechanical mean?
it is how a material will react to physical forces such as some materials becoming brittle when repeatedly bent or flexed
2 of 42
What does the term electrical mean?
it is a material's conductive properties such as insulation and resistanceE.G. Screwdriver's polymer handle(insulator) so it will not shock the user through the tip as metal used is a (conductor)
3 of 42
What does the term chemical mean?
How a material reacts to other chemicals such as how metals oxidise when exposed e.g. ferrous metals rusting
4 of 42
What does the term thermal mean?
how a material responds to different temperatures and boiling points such as the temperature ranges where thermoforming plastics can be shaped
5 of 42
What does the term magnetic mean?
Most ferrous(containing iron)as materials are attracted to magnets or can be magnetised. For a magnetic door catch
6 of 42
What does the term permeability mean?
the degree to which liquids or gases can pass through a material such as woods that have been varnished having low permeability to liquids and water resistance
7 of 42
What does the term aesthetic mean?
the visual properties of the surface/form of a material e.g. colour and shine
8 of 42
What does the term tactile mean?
the touch of a material such as texture
9 of 42
What is meant by the term strength?
the ability to withstand a constant external force without failing
10 of 42
What is meant by the term hardness?
the ability to resist wear and tear, scratching and dents
11 of 42
What is meant by the term toughness?
the ability to withstand blows or momentary shocks
12 of 42
What is meant by the term durability?
The ability to resist wear e.g. weathering over time
13 of 42
What is meant by the term elasticity?
The ability to bend and return to it's original shape
14 of 42
What is meant by the term plasticity?
The ability to permanently change shape or form, which applies to materials other than polymers
15 of 42
What is meant by the term malleability?
The ability to change shape in all directions while retaining integrity
16 of 42
What is meant by the term ductility?
The ability to permanently change shape by stretching along its length without snapping
17 of 42
When selecting materials what must be taken into consideration
1requirements for the user2function or conditions product is exposed to3materials can be found by using a materials database
18 of 42
what is meant by the term shape memory alloy
alloy of nickel and titanium that returns to original shape when hearted over 90C +contracts when current passed through itUSES: stents and dentures
19 of 42
what is meant by the term shape memory polymer
a variety of polymer(plastics) that deform when an electric voltage is applied or change in temp USES:valves or pumps for liquids where mechanical components are not desirable
20 of 42
what is meant by the term thermochromic inks
change in colour in response to changes in temp USES: forehead thermometer strips and to indicate temperature of a packaged food product in the food industry
21 of 42
what is meant by the term photochromic inks
change in colour in response to changes in light levelUSES: Light reacting sunglasses
22 of 42
what is meant by the term lenticular sheet
an embossed polymer sheet with optical fibres that make a surface appear deeper+can make images appear to flicker or moveUSES: used to provide visual/aesthetic interest to a surface such as the illusion of depth and 3d effects
23 of 42
what is meant by the term polymorph
small pellets which fuse when heated to 62C and can be moulded resulting in a tough polymerUSES: used by designers and engineers to prototype difficult shapes such as components and handles
24 of 42
what is meant by the term smart grease
A viscous gel which will uniformly control the movement between two friction surfacesUSES: used to dampen movement on volume control knobs slowing and smoothing rotation
25 of 42
what are the two types of synthetic polymer
thermoforming and thermosetting
26 of 42
what is meant by the term Nylon
used as a fibre in clothing+common+resists abrasion has low friction characteristics and good chemical resistance and is applied as a mechanical component such as gears, bushes and cams and in toothbrush files
27 of 42
what is meant by the term low and high density polyethylene
Tp is low density polyethylene is less expensive+High density polyethyle is more expensive and is available+injection and blow moulding bottles and containers
28 of 42
What is meant by the term polyethylene terepthalate
Hard,stiff strong and stable with low water absorption+good chemical resistanceUSES signs, drinks bottles and smart cards
29 of 42
what is meant by the term polyvinyl chloride
good resistance to chemicals and solvents+good tensile strength also resistant to water and fireUSES=rain,water and sewage pipes
30 of 42
what is meant by the term acrylic
hard with reasonable tensile strength and good resistance to UV light and weatherUSES=bathroom furniture and aircraft anopies
31 of 42
what is meant by the term polystyrene
poor resistance to UV light and commonly used USES toys, light fittings, computer cases
32 of 42
What is meant by the term polypropylene
high resistance to chemicals and highly flexible and resistant to stress USES=chemical containers and tanks, fuel cans
33 of 42
what is meant by the term acrylonitrile-butadiene-styrene(ABS)
durable, weather and chemical resistant rubber like so good impact resistanceUSES=boat hulls telephones
34 of 42
what is meant by the term melamine formaldehyde
Clear, hard and chemical resistant thermosetting resinUSES=electrical plugs, switches and sockets
35 of 42
what is meant by the term Urea formaldehyde
high tensile strength and surface hardness low water absorptionUSES=buttons, toilet seats and electrical fittings
36 of 42
what is meant by the term Phenol formaldehyde
A synthetic polymer with high hardness, good thermal stability and chemical resistanceUSES=laboratory worktops and billiard balls
37 of 42
what is meant by the term polyester resin
stable, low cost and easy to use, good chemical resistance and electrical propertiesUSES=glass reinforced for boat hulls, car body panels and printed circuit boards
38 of 42
what is meant by the term epoxy resin
high adhesive strength and mechanical properties as well as high electrical insulationIUSES=adhesives, coatings and printed circuit boards
39 of 42
how is rift sawn cut
pic
40 of 42
how is quarter sawn cut
pic
41 of 42
how is plain sawn cut
pic
42 of 42

Other cards in this set

Card 2

Front

what does the term mechanical mean?

Back

it is how a material will react to physical forces such as some materials becoming brittle when repeatedly bent or flexed

Card 3

Front

What does the term electrical mean?

Back

Preview of the front of card 3

Card 4

Front

What does the term chemical mean?

Back

Preview of the front of card 4

Card 5

Front

What does the term thermal mean?

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Design & Technology resources:

See all Design & Technology resources »See all Materials resources »