material and components 1

Question 1

functional performance

Answer 1

• how materials actually work and perform e.g. strength, weight, durability

Question 2

aesthetics

Answer 2

• shape form and colour

- links to a customers reaction and response when selecting a product to purchase

Question 3

Cost and availability

Answer 3

• increased availability, decreases cost
• increased cost increases quality
• cost involves transportation and processing materials

Question 4

properties and characteristics

Answer 4

• properties can be measured, characteristics can’t
• mechanical properties: strength, ductility, hardness
• physical properties: density, melting point
• chemical properties: corrosion resistant, hygroscopy
• manufacturing properties: formability, machinability, fusibility

Question 5

environmental considerations

Answer 5

6 R’s

• rethink, what materials and energy we use
• reduce, the materials we use
• reuse, materials and products
• repair, existing products
• recycle
• refuse, to use certain materials

Question 6

social, cultural and ethical factors

Answer 6

• there is a responsibility to ensure that other peoples quality of life and human rights are not compromised e.g. fair pay and decent working conditions and qol for residents nearby.
• inclusivity

Question 7

different physical properties of natural timber

Answer 7

• weather resistant
• chemical resistant
• impact resistant
• stiffness
• density

Question 8

different working properties of natural timber

Answer 8

• ease of machining
• ability to be glued
• ease of finishing

Question 9

advantages of manufacture boards

Answer 9

• available in large sheets
• relatively dimensionally stable - don’t twist/warp
• consistent properties across the board
• available pre-finished (laminated, foil or veneer)
• treated with flame retardant chemicals

Question 10

what are laminated boards

Answer 10

• > layers of wood glued using a synthetic resin

e. g. plywood, blockboard and laminboard

Question 11

what are compressed boards

Answer 11

• > made form chips and glued together

e. g. chipboard, MDF, HDF

Question 12

Developments in timber

Answer 12

• Neatflex -> flexible board for furniture
• cement-bonded particle board (overcomes durability problems)
• glulam -> strips of solid timber glued together
• engineered timber -> considerably stronger and more stable

Question 13

what is a ferrous metal

Answer 13

contains iron

Question 14

types of steels

Answer 14

• alloys of iron and carbon

> mild steel: up to 0.25%
medium carbon steel: 0.25-0.5%
high carbon steel: 0.5-1.5%

Question 15

cast iron

Answer 15

used for machine beds and vices
> cost effective but heavy
> rigid and strong in compression
> casts well and is easily machined

Question 16

Mild-steel, description, properties, uses

Answer 16

• 1.65% manganese, 0.6% silicone copper
• tough, ductile, malleable, poor resistance to corrosion
• uses: case hardening, structural material

Question 17

High-carbon steels, description, properties, uses

Answer 17

• 0.3-0.9% manganese
• High resistance to wear, brittle, poor resistance to corrosion
• uses: cutting tools and blades

Question 18

stainless steel, description, properties, uses

Answer 18

• 10.5% chromium (which produces a thin layer of oxide) preventing corrosion
• corrosion resistant, ductile, work hardening makes it magnetic
• cutlery, sinks, surgical instruments

Question 19

what are non-ferrous metals

Answer 19

they do not contain iron

Question 20

describe Aluminium

Answer 20

• low density, corrosion resistant
• soft with low strength and high ductility
• strengthened by alloying with silicon, manganese, magnesium, tin
• good thermal and electrical conductor
• uses: car bodies, ladders, windows, door handles

Question 21

describe Zinc

Answer 21

• galvanising
• corrosion resistant
• uses: watering cams etc.

Question 22

describe Copper

Answer 22

• soft and can be beaten into shape
• corrosion resistant and has great thermal/electrical conductivity
• uses: wires, heating application, plumbing

Question 23

describe Tin

Answer 23

• rarely used by itself

- coats tin cans

Question 24

describe Tungsten

Answer 24

• one of the toughest materials found in nature
• very dense, durable, resistant to corrosion and impossible to melt (3400 degrees c)
• highest tensile strength
• uses: drill bits, cutting tools, blades

Question 25

define non-ferrous metal alloys

Answer 25

they are metals mixed with other metals/substances to improve properties

Question 26

describe Brass

Answer 26

- Alloy of copper and zinc - Its bright gold-like appearance makes it suitable for decorative metalwork - melting point: 900-940 degrees C, density 8.4-8.73 c/cm3 - uses: locks, door handles, taps, musical instruments

Question 27

describe Bronze

Answer 27

- alloy of copper and tin (and aluminium, manganese) - tough and low coefficient of friction, tin content increases corrosion resistance/tensile strength - uses: electrical products, bearings

Question 28

describe aluminium alloys

Answer 28

- 99% aluminium, 0.1% mangenese and 0.5% silicon | - gives a strength-to-weight ratio of five times that of pure aluminium

Question 29

mechanical properties of metals

Answer 29

strength, hardness, toughness, elasticity, plasticity, brittleness, ductility and malleability - they are used as measurements of how metals behave under a load

Question 30

what is normalised steel

Answer 30

it has been softened by heating and cooling in air

Question 31

define polymer

Answer 31

many simple single units from which thermopolymers are made

Question 32

how polymers are made

Answer 32

- the units are joined together in long chains - the chains become entangled during a chemical reaction - a solid is formed that is both strong and rigid - Re-heated -> the forces of attraction between the molecules decrease, making material less rigid - 'thermo"

Question 33

Polymers have......

Answer 33

- excellent electrical and thermal insulators | - good strength to weigh ratio, flexibility, impact resistance

Question 34

thermo polymers

Answer 34

deform when heated, remoulded many times | suitable for vacuum forming, injection/blow moulding, recycling

Question 35

polystyrene (PS): safe working temp., characteristics, uses

Answer 35

- 80°C - stiff, hard, brittle - disposable cups - polystyrene: high impact/expanded (98% air)

Question 36

polyethylene (LDPE): safe working temp., characteristics, uses

Answer 36

- 75°C - flexible, soft, waxy - squeeze bottles, bin liners

Question 37

polyethylene (HDPE): safe working temp., characteristics, uses

Answer 37

- 75°C - fairly stiff, hard - bleach bottles, milk crates

Question 38

polymethyl methacrylate (PMMA): safe working temp., characteristics, uses

Answer 38

- 95°C - crystal clear, glossy, tougher than glass but sunlight degrades it over the years - car rear light units, illuminated signs

Question 39

polypropylene (PP): safe working temp., characteristics, uses

Answer 39

- 100°C - thin, stiff, hard, flexible, lightweight - carpets, banknotes

Question 40

polyvinyl chloride (PVC): safe working temp., characteristics, uses

Answer 40

- 95°C - plasticised: flexible, hosepipes - unplasticised: rigid, guttering/pipes

Question 41

acrylonitrile-butadiene-styrene (ABS): safe working temp., characteristics, uses

Answer 41

- 80°C - opaque, impact resistant, heavy - plug for vacuum, casing for cameras

Question 42

Polyethylene terephthalate (PET): safe working temp., characteristics, uses

Answer 42

- one of the strongest plastics - translucent, hard - fizzy drink bottles (can withstand the gas), containers

Question 43

polyamide (PA):

Answer 43

- heat resistant e.g. cooking utensils - natural: wool and silk - artificial: nylons - washers, cable ties

Question 44

thermosetting polymers

Answer 44

once the polymers have been shaped and hardened, they cannot be reshaped

Question 45

urea formaldehyde (UF): safe working temp., characteristics, uses

Answer 45

- 80°C - opaque, light in colour, hard/brittle - resin is inexpensive and heat resistant: used in plywood/chipboard - electrical fittings

Question 46

phenol formaldehyde (PF): safe working temp., characteristics, uses

Answer 46

- 120°C - opaque, dark in colour - heat and water resistant - laminant sheets, iron/saucepan handles

Question 47

melamine formaldehyde (MF): safe working temp., characteristics, uses

Answer 47

- 130°C - opaque, multi-coloured - cups, plates

Question 48

polyester resin: safe working temp., characteristics, uses

Answer 48

- 95°C - clear liquid resin, brittle, ease of handling, low cost, dimensionally stable - boats and vehicles

Question 49

epoxy resin: safe working temp., characteristics, uses

Answer 49

- 200°C, 2 resins in tubes/ 80°C, one tube has activator (adhesives) - high mechanical properties, temp an chemical resistance - hardwearing, durable finish and is an excellent insulator - 'potting' of electronic circuits

Question 50

mechanical properties and physical properties of metal

Answer 50

mechanical: - hardness -resistant to scratching - toughness -will not shatter - malleability -can be press formed into a shape physical: - resistant to corrosion - chemical resistant -will not degrade with detergents - electrical conductivity