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Flashcards in Materials Deck (29)
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1

Oak

Hardwood
Properties: hard, tough, durable, high density
Uses: furniture, boats, veneers
+ Finishes well
- Contains acid which corrodes steel

2

Mahogany

Hardwood
Properties: durable, medium density
Uses: indoor furniture + woodwork, window frames, veneers
+ Finishes well
+ Easy to work
- Prone to warping

3

Beech

Hardwood
Properties: hard, tough
Uses: workshop benches, toys, furniture, kitchen worktops
+ Turns well
+ Finishes well
- Prone to warping

4

Ash

Hardwood
Properties: tough, flexible, good elasticity
Uses: sports equipment, tool handles
+ Flexible
- Can become splintered

5

Pine

Softwood
Properties: lightweight
Uses: construction, floorboards, toys, decking
+ Grows fast
+ Nice colour
- Prone to warping
- Knots can fall out and leave holes

6

Plywood

Properties: very strong in all directions, resistant to splitting
+ Available in large sheets
+ Doesn't warp or twist
- Thin sheets are flexible and can warp if unsupported

7

Chipboard

Structure: waste products bonded using resins. No grain.
Properties: strong in all directions, not very water-resistant
+ Uses waste materials
- Soaks up water
- Edges chip and flake if unprotected

8

MDF

Properties: very dense, not affected by humidity (stability)
+ Thin sheets can be formed into 2D shapes
- Soaks up water

9

Hardboard

Properties: side smooth, underside textured
Sructure: fibres soaked in resin and compressed
+ Cheap
- No grain so not very strong

10

Manufactured boards

+ Dimensional stability
+ Can be painted or have veneers added
+ MDF, chipboard and hardboard can be made from waste

- Sharp tools needed
- Thin sheets bow if unsupported
- Edges must be sealed concealed
- Cutting and sanding creates hazardous particles

11

Mild steel

Properties: tough, malleable, magnetic
+ Cheap
+ Recyclable
+ Easy to work and join
- Will oxidise if unprotected
- Can only be case-hardened

12

Stainless steel

Properties: hard, tough, excellent corrosion resistance
+ Easily cleaned
+ Doesn't need finishing
+ Recyclable
+ High-lustre
- Hard to use and join
- Specialist welding equipment needed

13

Carbon steel

Properties: ductile
+ Recyclable
- Will oxidise if unprotected

14

Aluminium

Properties: lightweight, soft, ductile, malleable, conductive, corrosion resistance
+ Recyclable
+ Easily cast
+ Ductile
- Expensive
- Specialist welding equipment required

15

Copper

Properties: malleable, ductile, good conductor, corrosion resistant
+ Ductile
+ Easily soldered
+ Recyclable
- Will tarnish
- Expensive

16

Zinc

Properties: excellent corrosion resistance
+ Recyclable
- Brittle

17

Brass

Properties: corrosion resistant, casts well, good conductor
Composition: 65% copper, 35% zinc
+ Can be polished to a high-lustre finish
+ Tougher than copper
+ Recyclable
+ Easily cast and turned
- Expensive

18

Acrylic

Thermoplastic
Properties: lightweight, good electrical insulator, durable
+ Recyclable
+ Finishes well
+ Available in many colours
- Soft, scratches easily
- Poor chemical resistance

19

Polyethene

Thermoplastic
Properties: tough, chemically resistant, lightweight, electrical insulator, hard, tough, waterproof, durable
+ Recyclable
+ Cheap
- Expensive to recycle
- Dangerous fumes released when burnt

20

High-impact polystyrene

Thermoplastic
Properties: tough, high impact strength, electrical insulator
+ Many colours
+ Can be machined and painted
+ Recyclable
- Expensive
- Will not biodegrade

21

ABS

Thermoplastic
Properties: tough, high impact strength, lightweight, durable, scratch-resistant, electrical insulator, chemical resistance
+ Many colours
- Expensive

22

Polyester resin

Thermosetting plastic
Properties: electrical insulator, hard, brittle, heat and chemical resistance
+ Many colours
+ Water resistant
- Contracts on curing

23

Urea formaldehyde

Thermosetting plastic
Properties: stiff, hard, brittle, high tensile strength
+ Can be coloured
+ Very hard
- Toxic fumes given off when curing

24

Carbon fibre

Properties: lightweight, high tensile strength
Structure: fibres of carbon in a matrix (often epoxy resin)
+ High strength-to-weight ratio
+ High tensile strength
+ Can be woven in pretty patterns
- Very expensive
- Weak in compression and impact

25

Glass-reinforced plastic

Properties: high tensile and compressive strength, lightweight, durable
Structure: glass fibres in a matrix (polyester or epoxy resin)
+ Lightweight
+ Low maintenance
+ Can be formed into any shape
+ Good strength-to-weight ratio
+ Surface textures can be moulded
+ Durable
+ UV and sea salt resistance
- Hard to repair
- Time-consuming and labour-intensive to make
- Needs a mould
- Cutting produces harmful dust

26

Shape memory alloys

Properties: return to original shape when heated
Uses: glasses, braces, anti-scalding valves
+ Good elasticity and tensile strength
+ Lightweight
- Expensive

27

Photochromic paint

Properties: reversibly changes colour when in UV light
Uses: clothing, vehicles, textiles
- Amount of change depends on level of UV
- Ability decays over time

28

Reactive glass

Properties: changes colour in UV light or if voltage applied
Uses: transition lenses in glasses, windows
+ Replaces need for separate sunglasses (transition lenses)
- Expensive
- Windows are expensive to install

29

Carbon nanotubes

Uses: harden paint, strengthen plastics, conductor, medicine
+ Tensile strength
+ Electrical conductor
+ Tough
+ Chemically inert
- Expensive
- Toxic