1.2 Performance Characteristics Of Materials Flashcards
1
Q
In what direction do wood fibres grow along?
A
The length of the tree or branch
2
Q
What do wood fibres consist of?
A
Hollow cells (tracheids) supported by lignin resin.
3
Q
What part of the timber is strongest and which is weakest?
A
Timber is strong in the direction of the grain (along the grain) and weaker across the grain
4
Q
What are the two types of seasoning?
A
Air seasoning
Kiln seasoning
5
Q
How does air seasoning work?
A
Involves stacking the wood under a shelter, protected from the rain.
Air circulates between the planks to slowly remove the excess moisture
6
Q
Air seasoned wood is used for what type of products and why?
A
Air-seasoned wood is used for outdoor wooden products because it is seasoned to the same moisture content as its surroundings and therefore the wood will be less prone to defects.
7
Q
How does kiln seasoning work?
A
A more expensive but controlled method which is very quick and can take just a few weeks.
Planks are stacked onto trolleys and placed in the kiln where both temperature and humidity are controlled. Initially, the kiln atmosphere is very steamy but this is graduallly changed to become hotter and drier.
8
Q
Kiln-dried timber is used for what type of products and why?
A
Indoor products such as furniture will use kiln-seasoned wood because it has been seasoned to meet indoor conditions and will have a lower moisture content than air-dried wood.
9
Q
What happens is an unseasonaed plank is placed in a heated room?
A
It will twist, warp, cup or bow when drying out and cracks or gaps may appear.
10
Q
Seasoning the wood gives what advantages?
A
Greater immunity from decay and increased resistance to rot
Increased strength and stability
Helps preservatives to penetrate
Makes wood less corrosive to metals
11
Q
When ordering wood, how do designers lab it to show how it has been seasoned?
A
Oak air-dried (A-D) : suitable for exterior use
Oak kiln-dried (K-D) : suitable for interior use
12
Q
When does wood shrink and expand?
A
It expands and shrinks with changes in humidity (the amount of water present in the atmosphere ).
13
Q
How do you reduce the time taken to season wood to the correct moisture content ?
A
Trees should be felled in the winter when they grow less, have less sap and therefore contain least moisture.
The largest amount of shrinkage occurs after the tree is cut down and while it is being seasoned.
14
Q
In which direction does wood shrink ?
A
Almost no shrinkage in the direction of the wood’s grain (lengthwise).
Some shrinkage happens radially (perpendicular to the growth rings), with a greater amount of shrinkage occurring tangentially (along the curvature of the growth rings).
15
Q
What part of the wood loose the most moisture quickest?
A
The ends of the wood tend to lose moisture content more quickly than the core.
Sometimes cracks can appear in the plank ends.
16
Q
Why must care be taken when seasoning the wood?
A
So that the whole plank will shrink uniformly and usually once the wood has been fully seasoned, any cracks will close as the plank is now in equilibrium throughout.
17
Q
Why can seasoned wood be susceptible to shrinkage in a house ?
A
Seasonal changes in ambient humidity but this is less of a concern in modern homes where temperatures are fairly constant due to heating and air conditioning systems.
18
Q
What are the hardwoods?
A
Oak
Ash
Mahogany
Teak
Birch
Beech
19
Q
What are the softwoods?
A
Pine (European redwood)
Spruce
Douglas fir
Larch
Cedar
20
Q
What are the manufactured boards?
A
Plywood
Marine plywood
Aeroply
Flexible plywood
Chipboard
MDF
21
Q
What are the properties and characteristic of oak?
A
Hard
Tough
Attractive grain
Good weather resistance
Contains tannic acid which will corrode steel screws or fixings
22
Q
What are the properties and characteristic of ash?
A
Tough
Attractive open grain pattern which makes it more flexible
23
Q
What are the properties and characteristics of mahogany?
A
Can contain interlocking grain, making it more difficult to work
Rich dark red colour
24
Q
What are the properties and characteristics of teak?
A
Hard
Tough
Straight grain
Natural oils resist moisture
Acids and alkalis
25
What are the properties and characteristics of birch?
Hard
Straight closed grain
Resists warping
26
What are the properties and characteristics of beech?
Tough
Closed grain
Hard
Available in steamed (white colour) and unsteamed (pink tinge)
Does not impart a taste to food
27
What are the properties and characteristics of pine ?
Straight grain
Knotty
Can contain resinous knots
28
What are the properties and characteristics of spruce?
Straight grain
Resistant to splitting
29
What are the properties and characteristics of douglas fir?
Straight or slightly wavy grain
Few knots
Stable
Good resistance to corrosion
30
What are the properties and characteristics of larch?
Hard
Tough
Attractive grain patter fades to silver upon exposure outside
Good resistance to moisture
31
What are the properties and characteristics of cedar?
Straight grain
Con corrode ferrous metals due to acidic nature
Low density
Good sound damping
Good resistance to moisture
32
What are the properties and characteristics of plywood?
Thin layers of wood are placed and glued at 90 degrees to each other and compressed to form the board.
Good strength in all directions
No grain weakness
Always has an odd number of layers
33
What are the properties and characteristics of marine plywood?
Similar construction of plywood but is gap and void free and uses special set water and boil proof glue to provide resistance to moisture
Some higher quality marine plywood is also resistant to fungal attack
34
What are the properties and characteristics of Aeroply?
Plywood made from high quality timer such as birch
Available in very thin sheets
Lightweight
Each to bend around a support frame
35
What are the properties and characteristics of flexible plywood?
An odd number of layers glued together with two out layers made from open grained timer which allow the sheet to flex
Bent and glued around a former to achieve a solid shape
36
What are the properties and characteristics of chipboard?
Wood chips compressed with a resin such as urea formaldehyde
37
What are the properties and characteristics of MDF?
Compressed wood fibres although sometimes urea formaldehyde is added as an additional resin
Two smooth surfaces
Available in other standard grade or veneered with a layer of timer
38
What are the properties and characteristics of of veneers?
Thin slices of wood less than 3mm thick
39
What are the properties and characteristics of MF laminates?
Thin sheets of MF polymer
Hard
Tough
Chemical resistant
40
What are the uses of oak?
Furniture
Flooring
41
What are the uses of ash?
Tool handles
Sports goods
42
What are the uses of mahogany?
Indoor furniture
Shop fittings and cabinets
43
What are the uses of teak?
Outdoor furniture
Laboratory benches
44
What are the uses of birch?
Furniture
Indoor panelling
45
What are the uses of beech?
Chopping boards
Children’s toys
46
What are the uses of pine?
Construction work
Roof beams
47
What are the uses of spruce?
Indoor furniture
48
What are the uses of larch?
Garden furniture
Cladding
49
What are the uses of cedar?
Exterior cladding
Sheds
50
What are the uses of plywood?
Structural work
Desk tops
51
What are the uses of marine plywood?
Boat dashboards
Boat lockers
52
What are the uses of Aeroply?
Gliders
Laminated furniture
53
What are the uses of flexible plywood?
Laminated furniture
Curved panels
54
What are the uses of chipboard ?
Kitchen worktops
Flat pack furniture
55
What are the uses of MDF?
Model making
Furniture items such as bookcases
56
What are the uses of veneers?
Decorative coverings for manufactured boards
57
What are the uses of MF laminates?
Decorative covering for chipboard for kitchen worktops
58
What part of a wood can be a hazard and form a health risk to workers?
The dust and the sap
59
The toxicity of a wood depends on what?
The species of the wood
60
Due to the dust of woods, what has to be put in place in industry to stop the health risks?
Employers should ensure that there is adequate personal protection equipment, extraction and ventilation systems in place
61
What is rough sawn wood?
The wood comes directly from seasoning and has rough surfaces produced from initial conversion.
Rough sawn wood will have nominal sizes rather than accurate finished sizes.
62
What does PSE stand for?
Planed square edge
63
What is planed square edge wood?
Wood that has only one she that is planed accurately and the rest are rough sawn.
Planing removed about 3mm from the original nominal size.
64
What does PAR stand for ?
Planed all round
65
What is planed all round wood?
Wood that has the sides and edges that are all planed square, straight and level, leaving a smooth finish and is ready to use.
The PAR board is about 3mm smaller all round than the original rough sawn nominal size.
66
When joining planks of wood, what direction should the grains be ?
The end grains must go in opposing directions to each other. This is to ensure that the internal forces of the wood do not pull the wood in one direction and the top is joined in equilibrium.
67
What are the advantages of manufactured boards?
Available in long, wide birds of uniform thickness and quality
Very stable, not affected by room temperature and humidity as much as solid wood
Uniform strength across the board, no grain problems
Difficult to split and available in flexible thin sheet form
Generally less expensive than solid wood of a similar size
Veneers can be applied to the surface for enhanced aesthetics
68
What are some examples of mouldings ?
Skirting boards
Wooden trims
69
What are metals?
Naturally occurring material and is mined from the ground in the form of ore.
70
How is raw metal extracted from the ore?
A combination of crushing, smelting and heating, with the addition of chemicals and huge amount of electrical energy
71
Can metals be recycled ?
Most metals can be recycled, saving natural resources and limiting the amount of materials imported from abroad.
72
What are the non-ferrous metals?
Aluminium
Copper
Zinc
Silver
Gold
Titanium
Tin
73
What are the ferrous metals ?
Low carbon steel
Medium carbon steel
Cast iron
74
What are the ferrous alloys?
Stainless steel
High speed steel (HSS)
Die steel ( tool steel )
75
What are the non-ferrous alloys?
Bronze
Brass
Duralumin
Pewter
76
What are the properties and characteristics of aluminium?
Lightweight
Ductile
Malleable
Corrosion resistant
Electrical and thermal conductor
Can be metal inert gas and tungsten inert gas heat welded
77
What are the properties and characteristics of copper?
Ductile
Malleable
Tough
Corrosion resistant
Good electrical and thermal conductor
Can be soldered and brazed
78
What are the properties and characteristics of zinc?
Low melting point
Good corrosion resistance
79
What are the properties and characteristics of silver?
Malleable
Ductile
Corrosion resistant
Can be soldered
80
What are the properties and characteristics of gold?
Malleable
Ductile
Corrosion resistant
Can be soldered
81
What are the properties and characteristics of titanium?
Hard
Similar strength to steels but more lightweight
High resistance to corrosion
82
What are the properties and characteristics of tin?
Ductile
Malleable
Low melting point
Corrosion resistant
83
What are the properties and characteristics of low carbon steel?
Ductile
High tensile strength
Tough
Malleable
Poor resistance to corrosion
84
What percentage of low carbon steel is carbon content ?
0.15-0.30%
85
What are the properties and characteristics of medium carbon steel?
Harder than low carbon steel but less ductile, malleable and tough
86
What percentage of medium carbon steel is the carbon content ?
0.30-0.70%
87
What are the properties and characteristics of cast iron ?
Hard outer skin but brittle core
Good under compression
88
What percentage of cast iron is carbon ?
3.5%
89
What are the properties and characteristics of stainless steel?
Tough
Hard
Corrosion resistant
90
What are the properties and characteristics of high speed steel?
Hard
Tough
High level of resistance to frictional heat
91
What are the properties and characteristics of die steel?
Hard
Tough
92
What are the properties and characteristics of bronze?
Tough
Corrosion resistant
Can be cast
93
What are the materials in bronze and what percentages do they make up ?
90% copper
10% tin
94
What are the properties and characteristics of brass?
Corrosion resistant
Good electrical and thermal conductor
Low melting points
Casts well
95
What are the materials in brass and what percentages do they make up ?
65% copper
35% zinc
96
What are the properties and characteristics of duralumin?
Equivalent strength properties to low carbon steel but more lightweight and ductile
Becomes harder as it is worked
97
What are the properties and characteristics of pewter?
Malleable
Low melting point
Casts well
98
What materials make up pewter and what are their percentages?
85-99% tin
The remainder consists of copper and antimony
99
What are the uses of aluminium?
Drinks cans
Aircraft bodies
Bike frames
100
What are the uses of copper?
Electrical wire
Printed electrical circuits
Water pipes
101
What are the uses of zinc?
Galvanising steel as a protective coating for dustbins
Buckets
Farm gates
102
What are the uses of silver?
Jewellery
Cutlery
Plating other materials
103
What are the uses of gold?
Jewellery
Electronic components
Connectors
104
What are the uses of titanium?
Joint replacements
Tooth implants
Spectacle frames
105
What are the uses of tin?
Soft solder
Coatings for food cans
Rarely used in pure form
106
What are the uses of low carbon steel?
Nuts
Bolts
Car bodies
107
What are the uses of medium carbon steel?
Springs
Gardening tools
108
What are the uses of cast iron?
Disc brakes
Machine karts
Engine blocks
109
What are the uses of stainless steel?
Sinks
Kitchenware
Cutlery
110
What are the uses of high speed steel?
Tool blades
Drill bits
Milling cutters
111
What are the uses of die steel?
Blanking punches and dies
Extruder dies
Fine press tools
112
What are the uses of bronze?
Statues
Coins
Bearings
113
What are the uses of brass?
Boats fittings
Door furniture
Casts valves and taps
Ornaments
114
What are the uses of duralumin?
Aircraft parts
Vehicle parts
115
What are the uses of pewter?
Tankards
Flasks
Goblets
Photo frames
116
If a stricken from is more complex or uses more material, what does this mean for the price ?
It is more expensive
117
What are the 5 stock forms for metals ?
Sheet
Plate
Bar
Tube
Structural
118
How are polymers made?
Via fractional distillation of crude oil which produces fractions containing a mixture of hydrocarbons.
The hydrocarbons undergo cracking, which breaks the large hydrocarbons down into smaller and more useful forms.
Polymers are made by either the polymerisation or polycondensation process, in which monomers are linked together to form long chains of molecules.
119
What are the three classification groups of polymers ?
Thermoplastics
Thermosetting polymers
Elastomers
120
What are bio-based polymers designed for?
To have a much shorted degradation time than the synthetic polymers made from crude oil.
121
Why are polymers considered to be self-finishing ?
Because they can be pigmented during the manufacture process to give colour and therefore require no additional secondary finishing processes.
122
What are the available stock forms for polymers ?
Granules
Sheet
Film
Rods (and other extruded forms)
Tubes
Bars
Foam
Powder
123
What is meant by the safe working temperature of polymers ?
It should be noted because it is the temperature deemed safe for processing without possible degradation of the polymer properties
124
What are the 9 thermoplastics?
Low density polyethylene (LDPE)
High density polyethylene (HDPE)
Polypropylene (PP)
High impact polystyrene (HIPS)
Acrylonitrile butadiene styrene (ABS)
Polymethyl-methacrylate (PMMA)
Nylon
Rigid polyvinyl chloride (uPVC)
Flexible polyvinyl chloride (PVC)
125
What are the properties and characteristics of LDPE?
Very tough
Good chemical resistance
Weatherproof
Available in translucent
Low levels of rigidity
126
What are the properties and characteristics of HDPE?
Available in translucent form
Weatherproof
Tough
Good chemical resistance
127
What are the properties and characteristics of PP?
Available in translucent
Good chemical resistance
Tough
Good fatigue resistance
128
What are the properties and characteristics of HIPS?
Hard
Rigid
Available in translucent
Tough
129
What are the properties and characteristics of ABS?
Extremely tough
Hard
Available in opaque
130
What are the properties and characteristics of PMMA?
Tough
Hard
Good chemical resistance
Available in translucent
131
What are the properties and characteristics of nylon ?
Tough
Corrosion resistant
Good temperature resistance
Low coefficient of friction
132
What are the properties and characteristics of uPVC?
Rigid
Opaque
Tough
Hard
Good weathering resistance
Good chemical resistance
Fire retardant
133
What are the properties and characteristics of PVC?
Available in translucent
Tough
Flexible
Good weathering resistance
Good chemical resistance
134
What are the uses of LDPE?
Squeezy detergent bottles
Toys
Carrier bags
Bin liners
General packaging
Food wrap film
Food trays
135
What are the uses of HDPE?
Chemical drums
Jerry cans
Toys
Household and kitchenware
Long life carrier bags
Buckets
Bowls
136
What are the uses of PP?
Rope
Folders
Folio cases
Food containers
Medical equipment
Hinged containers lids
137
What are the uses of HIPS?
Yoghurt pots
Refrigerator linings
Single use drink cups
Toilet seats
Instrument control knobs
138
What are the uses of ABS?
Telephone handsets
Lego bricks
Rigid luggage
Domestic appliances
Calculator casings
139
What are the uses of PMMA?
Car light casings
Computer numerically controlled laser cut items
Lighting units
Lighting covers
Baths
140
What are the uses of nylon ?
Bearings
Gears
Curtain rails
Textiles
141
What are the uses of uPVC?
Window frames
External doors
Guttering and down pipes for buildings
Water service pipes
Bank cards
142
What are the uses of PVC?
Hose pipes
Cable insulation
Medical grade tubing
Inflatable products
143
What are the 4 thermosetting polymers?
Urea formaldehyde (UF)
Melamine formaldehyde (MF)
Polyester resin
Epoxy resin
144
What are the properties and characteristics of urea formaldehyde?
Hard
Heat resistant
Good electrical insulator
Brittle
145
What are the properties and characteristics of melamine formaldehyde ?
Hard
Opaque
Tough
Heat resistant
Food safe
Chemical resistant
146
What are the properties and characteristics of polyester resin?
Rigid
Heat resistant
Chemical resistant
Brittle
147
What are the properties and characteristics of epoxy resin?
Rigid
Clear
Hard
Tough
Chemical resistant
148
What are the uses of urea formaldehyde?
Electrical fittings
Adhesives
149
What are the uses of melamine formaldehyde?
Decorative laminates
Picnic ware
Buttons
150
What are the uses of polyester resin?
Castings
Used in lay-up process for glass reinforced plastic for boat hulls
Car parts
Chair seats
151
What are the uses of epoxy resin?
Adhesives
Surface coatings
Encapsulation of electrical components
Cardiac pacemakers
152
What are elastomers?
The ability to be stretched to many times their original length and then, upon the removal of the tension, return to their original shape.
153
What are the four elastomers?
Natural rubber
Butadiene rubber (BR)
Neoprene
Silicone
154
What are the properties and characteristics of natural rubber?
High tensile strength
Low elongation
Good hardness compared to other elastomers
Tough
Electrical insulator
Good cold resistance
155
What are the properties and characteristics of butadiene rubber?
Tough
Excellent weather resistance against friction
Good thermal resistance against friction
Electrical conductor
156
What are the properties and characteristics of neoprene?
Good thermal resistance
Toughness
Good oil and chemical resistance
Excellent weather resistance
Good abrasion resistance
Electrical insulator
157
What are the properties and characteristics of silicone?
Good flexibility at low temperatures
Poor abrasion resistance
Good thermal resistance
Good resistance to temperature extremes
Good weather resistance
Good lubricating qualities
Electrical insulator
158
What are the uses of natural rubber?
Automotive industry such as tyres, tubes, hoses, gaskets, belts, balloons, toys and footwear
159
What are the uses of butadiene rubber?
Vehicle tyres, shoe soles, toys, conveyor belts, water and pneumatic hoses
160
What are the uses of neoprene?
Wetsuits
Laptop cases
Industrial wire insulation
161
What are the uses of silicone?
Flexible ice cube trays and bakeware
Cooking utensils
Seals for refrigerators
Sealants
Tubing for drug delivery systems
162
What are most polymers produced from ?
Non-renewable resources such as crude oil, which do not break down easily
163
What is an alternative resource to crude oil that you can use to make polymers?
Natural and renewable resources such as wood (cellulose), vegetable oils, sugar and starch
164
Due to technological advancements, what does this mean for the manufacture of polymers?
Manufacturers are making use of bio-polymers and biodegradable polymers due to an increased environmental awareness.
165
What two categories can bio-polymers be split into?
Natural
Synthetic
166
What are natural bio-polymers?
Made from natural materials such as cellulose, starch and polysaccharides
167
What are synthetic bio-polymers?
Made from renewable resources but chemically engineered to break down more quickly.
168
When does polymer degradation occur?
When the polymer undergoes a significant change in properties due to the influence of chemicals, heat or light.
169
What are the two main descriptions for biodegradable polymers?
1. The polymer is made from finite resources such as crude oil. The polymer contains additives that cause it to degrade more quickly than traditional polymers, for example in less than 5 years. Degradation occurs in the presence of light (photodegradable), oxygen (oxy-degradable) or water (hydro-degradable).
2. Degradation occurs because of the action of micro-organisms which convert the material into water, carbon dioxide, biomass and possibly methane. Some polymers degrade in a few weeks while others may take several months. The ability of a polymer to biodegrade is dependent on the structure of the polymer rather than the origin of the raw material.
170
What are oxy-degradable polymers and how do they biodegrade?
The polymer break down into a fine powder with exposure to oxygen and is subsequently degraded by the action of micro-organisms. The length of the time for oxy-degradable polymers to degrade can be ‘programmed’ during the manufacture and ranges from a few months to a few years.
171
What are photodegradable polymers and how do they biodegrade ?
The polymer bonds are weakened and the polymer breaks down with exposure to ultraviolet light, which as UV rays from sunlight.
172
What industry are photodegradable polymers often used in?
The agriculture industry where the ground is covered by the polymer sheet, which acts as a mulch to prevent weed grouts when growing crops. As the sheet slowly degrades, weed growth halts, therefore decreasing the need for herbicides. The sheet also helps hold water in the ground and extends the growing season by insulating the ground.
173
What are hydro-degradable polymers and how do they work?
The polymer breaks down with exposure to water and subsequently micro-organisms. Hydro-degradable polymers tend to degrade more quickly than oxy-degradable polymers.
174
What are the 7 implications of the use of bio-polymers and biodegradable polymers?
1. Biodegradable polymers can produce methane gas when they decompose in landfill. Methane gas is a greenhouse gas, which contributes to global warming.
2. Biodegradable polymers can take high temperatures to decompose and may leave behind toxic residues.
3. Natural bio-polymers need land to grow the crops to make them. This could result in traditional agricultural land being lost to ‘grow polymers’. The loss of land could lead to an increase in food costs for the consumer.
4. Natural bio-polymers could be made from genetically modified crops.
5. Bio-polymers and biodegradable polymers cannot be recycled. Their use may not encourage people to recycle and may contribute to a throw-away culture.
6. Bio-polymers and biodegradable polymers can be processed in the same way as thermoplastics.
7. The terms ‘bio-polymer’ and ‘biodegradable polymer’ have different meaning which may help confusing to the lay person, potentially making it harder for them to make a positive environmental choice when shopping.
175
What are the 7 biodegradable polymers?
Corn starch polymer
Potatopak
Biopol
Polylactide
Polyhydroxyalkanoate
Lactide
Glycolide
176
What type of bio-polymer is corn starch polymer?
Natural
177
What type of bio-polymer is potatopak ?
Natural
178
What type of bio-polymer is biopol?
Natural
179
What type of bio-polymer is polylactide acid?
Synthetic
180
What type of bio-polymer is lactide?
Synthetic
181
What type of bio-polymer is polyhydroxyalkanoate?
Natural
182
What type of bio-polymer is glycolide?
Synthetic
183
What is the source of corn starch polymer?
Make from high starch vegetables such as corn, potatoes and maize
184
What is the source of potatopak?
Made from potato starch
185
What is the source of biopol?
Made from bacteria grown in cultures
186
What is the source of polylactide acid?
Made from corn kernels or cane sugar, fermented to produce lactic acid, then synthesised to produce polylactic acid
187
What is the source of polyhydroxyalkanoate?
Made from bacteria grown in cultures
188
What is the source of lactide?
PLA and cellulose based
189
What is the source of glycolide?
PLA and cellulose
190
What are some uses of corn starch polymer?
Packaging products
Straws
Vending cups
191
What are some uses of potatopak?
Single use food items such as bowls
Packaging beads
Bin bags
192
What are some uses of biopol?
Packaging products such as film carrier bags
Vending cups
Nappies
193
What are some uses of polylactide acid?
Packaging
Single use bottles
Carrier bags
Plant pots
194
What are some uses of polyhydroxyalkanoate!
Medical uses such as slow release medication patches
Films
Screws
195
What are some uses of lactide?
Biomedical applications
Slow release medication
bone repair fixings
196
What are some uses of glycolide?
Food film
Bags
Bins bags
Flower wrap
197
What is a composite material?
A material comprised of two or more different materials, resulting in a material with enhanced properties.
198
What are the 8 composite materials?
CFRP - carbon fibre reinforced plastic
GRP - glass reinforced plastic
Tungsten carbide
Aluminium composite board
Concrete
Reinforced concrete
Fibre cement
Engineered wood
199
What is carbon fibre reinforced plastic?
Carbon fibres mixed with polyester resin or epoxy resin
200
What is glass reinforced plastic?
Glass fibres mixed with polyester resin
201
What is tungsten carbide?
A cermet (mixture of ceramic and metal particles)
Ceramic tungsten and cobalt metal
202
What is aluminium composite board ?
Aluminium sheets with polyethylene core.
203
What is concrete?
Cement powder, sand, aggregate particles mixed with water
204
What is reinforced concrete?
Cement powder, sand, aggregate particles and low carbon steel robs mixed with water
205
What is fibre cement ?
Cement powder, sand, aggregate particles and polymer or steel fibres mixed with water
206
What is engineered wood?
Timer laminates and MF adhesive
207
What are the properties of CFRP?
Lightweight
Corrosion resistant
Tough
Hard
Good compressive strength
Low thermal expansion
208
What are the properties of GRP?
Lightweight
Correction resistant
Tough
Hard
Low thermal expansion
Good compressive strength
209
What are the properties of tungsten carbide ?
Hard
Tough
Resistant to high temperatures
Corrosion resistant
210
What are the properties of aluminium composite board?
Lightweight
Rigid
Tough
Malleable
Good thermal and sound insulation
Good vibration damping
211
What are the properties of concrete?
Hugh compression strength
Low tensile strength
Few surface defects
Easy to mould
212
What are the properties of reinforced concrete?
High compression and tensile strength
Consistency across the structure
Few surface defects
Fire resistant
213
What are the properties of fibre cement ?
Lighter in weight than reinforced concrete
Hard
Tough
Good at low temperatures and freeze/thaw situations
214
What are the properties of engineered wood?
Good aesthetics
Natural alternative to reinforced concretes
More lightweight than concrete alternatives
Fire resistant
Good structural stability
Corrosion proof
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What are the uses of CFRP?
Sports equipment
Racing car bodies and parts
Helmets
Prosthetics
216
What are the uses of GFP?
Boat hulls
Ping liners
Kayak shells
Sports car bodies
217
What are the uses of tungsten carbide?
Cutting tools such as drill bits, lathe tool tips, router bits
Kitchen knives
218
What are the uses of aluminium composite board?
Sound-proofing panels in cars, buildings and boats
Signage
219
What are the uses of concrete?
Pathways
Beams
Blocks
Driveways
House foundations
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What are the uses of reinforced concrete?
Buildings
Bridge piles and bridge spans
Retaining walls
Grid floors
221
What are the uses of fibre cement ?
Suspended floors
Complex geometric shapes
Pathways
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What are the uses of engineered wood?
Beams
Bridges
Domes
Arches
Decking
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What is a smart material?
Material whose physical properties change in response to an input or change in environment, such as electricity, pressure, temperature or light.
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What are 3 common uses of shape memory alloys?
1. Response in change in temperature, for example triggers for fire alarm systems, sprinkler systems, hot water valves in showers, industrial greenhouse windows
2. Repair of the malformed or damaged produced, for example spectacle frames which have been diapered can return to their original shape when heated to the transition temperature.
3. A movement response from an electrical signal, for example artificial muscles in robot arms, electric door locks
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What are the 6 smart materials ?
Shape memory alloys
Thermochromic pigment
Phosphorescent pigment
Photochromic pigment
Electroluminescent wire
Piezoelectric material
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How do shape memory alloys work?
Changes in shape in response to a change temperature or electrical input
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How does thermochromic pigment work?
Changed colour in response to temperature change
228
How does phosphorescent pigment work?
Absorbs light energy during the day and re-emits the light energy when it is dark.
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How does photochromic pigment work?
Changes colour with light intensity
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How does electroluminescent wire work?
Thin copper wire coated in phosphorescent material which glows in response to an alternating current
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How does piezoelectric material work?
Gives off a small electrical charge when deformed.
Increases in size when an electrical current is passed through it.
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What are the uses of shape memory alloys?
Dental braces
Self closing windows
Aeroplane wing flaps
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What are the uses of thermochromic pigment?
Room thermometers
Medical thermometers for children
Colour change mugs and kettles
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What are the uses of phosphorescent pigment?
Fire exit signs
Glow in the dark products
Night lights
235
What are the uses of photochromic pigment?
Welding goggles
Reactive spectacle lenses
Security markers that show under UV light
236
What are the uses of electroluminescent wire?
Glow bracelets
Interweaving for clothing
Home decoration
Outdoor decorative lighting
237
What are the uses of piezoelectric material?
Airbag sensors in cars
Lighters for barbecues
Pressure sensors
238
How are modern materials developed?
Through the invention of new or improved processes.
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What are the 4 modern materials?
Kevlar
Precious metal clay (PMC)
High density modelling foam
Polymorph
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What are the features of kevlar?
Aramid fibres with high cut and heat resistant properties
241
What are the features of precious metal clay?
Clay consistency material made up of fine metal particles.
Works like ceramic clay, easily mouldable, easy to shape and form, sets hard once fired with a kiln or butane torch.
Inexpensive compared to solid metals such as silver.
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What are the features of high density modelling foam?
Polyurethane closed cell foam blocks or sheets.
Lightweight, easy to work using traditional woodworking tools, CNC miller/router, sands easily to allow intricate shapes and forms to be created.
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What are the features of polymorph?
Granules which become mouldable at about 60 degrees Celsius.
Can be heated in water or with a hair dryer. Solidifies at room temperature.
Available in liquid form. Liquid at room temperature and solidifies at 2 degrees Celcius.
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What are the uses of kevlar?
Body armour
Cut-proof gloves and aprons
Aerospace applications
Surfboard components
Puncture-resistant bicycles tyres
245
What are the uses of precious metal clay?
jewellery
decorative items
small sculptures
fobs
246
What are the uses of high density modelling foam?
3D modelling
Prototypes
247
What are the uses of polymorph?
Modelling
Shaping ergonomic handles
Prototype mechanical parts
248
What processes can you do with papers and boards?
Scoring
Cutting
Folding
249
What is the original source of paper? What colour is it?
wood pulp, which is grey in colour
250
How is grey wood pulp turned into a whiter colour?
During manufacture, bleaches are added to transform the grey pulp into a white paper.
251
What are the 13 different types of paper?
Layout paper
Cartridge paper
Tracing paper
Bleed-proof paper
Treated paper
Watercolour paper
Corrugated card
Bleached card
Mount board
Duplex card
Foil backed and laminated card
Metal effect card
Moulded paper pulp
252
What are the properties and characteristics of layout paper?
thin translucent paper with a smooth surface
253
What are the properties and characteristics of cartridge paper?
Off-white paper usually with a slightly textured surface
254
What are the properties and characteristics of tracing paper?
translucent paper slightly thicker than layout paper
255
What are the properties and characteristics of bleed-proof paper?
Similar to cartridge paper but has a bleed-proof layer on one side so colours do not run
256
What are the properties and characteristics of treated paper?
Plain paper with a clear binder or dye layer applied to help hold the image on the paper surface and brighten the image. Surface sheens such as high gloss or matt available.
257
What are the properties and characteristics of watercolour paper?
Available in absorbent, smooth, hot-pressed or the more textured cold-pressed and heavily textured rough.
258
What are the properties and characteristics of corrugated card?
Usually with carton board outer layers and a corrugated middle layer, giving the material the ability to provide protection against impact.
259
What are the properties and characteristics of bleached card?
Chemically treated to brighten the surface to make it suitable for high-quality printing.
260
What are the properties and characteristics of mount card?
Made from compressed fine cotton fibres to produce a rigid board
261
What are the properties and characteristics of duplex card?
Made up of two layers of paper, with the exterior often coated to make it more water-resistant and to give it a glossy sheen and waxy feel.
262
What are the properties and characteristics of foil backed and laminated card?
Card with polymer film or foil applied to either one side or both sides to provide a water resistant and/or heat insulating layer.
The foil or laminate layer must be removed before recycling the paper pulp.
263
What are the properties and characteristics of metal effect card?
High quality card with a thin metal effect layer applied to the outer surface for enhanced aesthetics.
Can be embossed.
264
What are the properties and characteristics of moulded paper pulp?
Recycled paper pulp moulded when wet and dried to a specific shape.
Usually smooth on the visible inside surface and rough textured on the outer surface.
