unit 5 composite materials

Question 1

mechanical properties

Answer 1

tensile and compressive strength
stiffness and toughness
plasticity and elasticity
ductility and malleability

Question 2

physical properties

Answer 2

mass,wieght,volume
density and harness
electrical and thermal conductivity

Question 3

what is tungsten carbide

Answer 3

composite material
made from ceramic and metal
hard, rigid,impact resistant
used in high speed cutting tools

Question 4

carbon fiber

Answer 4

lightweight, high tensile strength
corrosion/chemical resistant
stable in hot conditions
used in racing cars

Question 5

glass reinforced platic

Answer 5

strong in tension
little compressive strength
lightweight
uv/corrosion/water resistant

Question 6

aluminium composite boards

Answer 6

easy to cut
stable, durable,lightweight
range of colours, wont wrap/wrinkle
used in wall panels

Question 7

fiber cement

Answer 7

was made from cement, asbestos
now made from cellulose and synthetic fibres
lightweight,durable,weather/chemical/rust resistant
used in cladding

Question 8

concrete

Answer 8

made from air, cement,water,sand,gravel
heavy, high compressive strength,cheap
used in buildings

Question 9

steel reinforced concrete

Answer 9

used in high rise buildings, bridges and multi story car parks

Question 10

smart material

Answer 10

one or more properties that is dramatically altered by an external stimulus

Question 11

shape memory alloys

Answer 11

programmed to remember specific shape at certain temperature
expensive
weather/temp/electrical current stimuli

Question 12

thermochromic pigment

Answer 12

changes colour/opoacity with change in temp
temp stimuli

Question 13

phosphorescent pigment

Answer 13

glow in the dark
material absorbs energy from light and emits light in the dark
used in toys paints stickers
light stimuli

Question 14

photochromic pigment

Answer 14

smart material that changed colour/opacity with uv light in a reversible reaction
used in spectacles, clothing
light stimuli

Question 15

electroluminescent wire

Answer 15

copper wire coated in phosphor glows when alternative current is applied
flexible, can be used outdoors
used in lighting,bikes,vechicles
electrical current stimuli

Question 16

piezoelectric materials

Answer 16

convert mechanical energy into electrical
can be stored
used to create spark in lighters
pressure stimuli

Question 17

What kind of external stimuli might affect a smart material?

Answer 17

Temperature
Moisture
Light Levels
Pressure

Question 18

what is kevlar

Answer 18

high performance aramid fiber

Question 19

properties of kevlar

Answer 19

bullet proof, heat and chemical resistant,lightweight,hardwearing,strong,stiff

Question 20

what is polymorph

Answer 20

thermoplastic which becomes malleable when heated to 62

Question 21

properties of polymorph

Answer 21

tough durable non toxic biodegradable low melting point

Question 22

uses of polymorph

Answer 22

enhanced ergonomic designs
moulds and gum shields

Question 23

what is precious metal clay made of

Answer 23

from precious metal particles held in a water based non toxic binder

Question 24

properties of pmc

Question 25

What does PMC stand for?

Answer 25

Precious Metal Clay

Question 26

What are the uses of PMC?

Answer 26

used to set stones and join PMC parts

Question 27

What are the properties of HDMF?

Answer 27

lightweight and easy to handle
soft so cuts easy
dented easily
paint and glue will dissolve hdmf
holds good surface detail and fillers

Question 28

what does HDMF stand for?

Answer 28

High Density Modelling Foam

Question 29

What is HDMF used for?

Answer 29

makes molds for vacuum forming

Question 30

What is shape memory alloys used for?

Answer 30

Nitinol

Question 31

example of thermochromic pigment?

Answer 31

varnishes
kids cup

Question 32

Phosphorescent examples

Answer 32

fire exit signs

Question 33

electroluminescent examples

Answer 33

veichles and bikes

Question 34

piezoelectric examples

Answer 34

crystal
ceramic
bone