Technical Principles Flashcards
(82 cards)
1
Q
What’s compressive strength?
A
The ability to withstand being crushed or shortened by pushing forces.
2
Q
What’s tensile strength?
A
The ability to resist stretching or pulling forces
3
Q
What’s bending strength?
A
The ability to resist forces that may bend the material
4
Q
What’s shear strength?
A
The ability to resist sliding forces on a parallel plane.
5
Q
What’s torsional strength?
A
The ability to resist twisting forces from applied torsion
6
Q
What’s hardness
A
The ability to resist abrasive wear, such as scratching or surface indentation
7
Q
What’s toughness
A
The ability to absorb impact force without fracture
8
Q
What’s plasticity
A
The ability to be permanently deformed and retain the deformed shape
9
Q
What’s ductility
A
That ability to be drawn out under tension, without cracking
10
Q
What’s malleability
A
The ability to withstand deformation by compression without cracking
11
Q
What’s elasticity
A
The ability to be deformed and return to the original shape when the force is removed
12
Q
What’s the density of a material?
A
The mass of the material in a standard volume of space.
13
Q
What’s fusibility?
A
The ability of a material to be fused or converted to a solid to liquid/molten state.
14
Q
What’s magnetism?
A
The natural force of an object that causes the material to attract iron or steel
15
Q
What’s corrosion/degradation resistance?
A
The ability of the material to withstand environmental attack or decay
16
Q
What’s an electrical conductor?
A
Something that allows the flow of electrical current through the material.
17
Q
What’s an electrical insulator?
A
Something that doesn’t allow the flow of electricity through the material
18
Q
What’s a thermal conductor?
A
Something that allows the transfer of heat energy through a material.
19
Q
What’s a thermal insulator?
A
Something that prevents the transfer of heat through a material
20
Q
What’s thermal expansion?
A
The increased in material volume in response to heat input
21
Q
What’s the definition of opaque?
A
Prevents light from travelling through
22
Q
What’s does it mean when something is translucent?
A
It allows light through but diffuses the light so objects appear blurred
23
Q
What’s does it mean when something is transparent?
A
It allows light to pass through easily, so you can see clearly through the material
24
Q
What are mechanical properties?
A
Properties associated with how a product reacts to an external force
25
What’s a physical property
Properties associated with the actual make-up or structure of the material
26
What are the 3 types of metal classifications?
- Ferrous
- non-ferrous
- alloy
27
What’s a ferrous metal?
A metal containing mostly iron and carbon.
- are magnetic and will rust
28
What are some examples of ferrous metals?
- low carbon steel
- medium carbon steel
- cast iron
29
What’s a non-ferrous metal?
A metal that doesn’t contain iron.
- not magnetic and don’t rust
30
What are some non-ferrous metals?
- aluminium
- copper
- zinc
- silver
- gold
- titanium
- tin
31
What’s an alloy?
A metal made up of two or more metals, or combined two or more elements, one of which must be a metal.
- they can be ferrous or non-ferrous
32
What are some example of alloys?
Ferrous and non-ferrous
Ferrous
– stainless steel, die steel
Non-ferrous
– bronze, brass, duralumin, pewter
33
What’s a hard wood?
A wood from broad-leafed trees (deciduous)
- slow growing and loose leaves in autumn
34
What’s a softwood?
A wood from a coniferous tree (cone bearing)
- fast growing and evergreen
35
What’s manufactured board?
A man-made wood-based composite material
36
What’s are some examples of a hardwood?
Oak, ash, mahogany, teak, birch, beech
37
What are some examples of soft woods?
Pine, spruce, Douglas fir, redwood, cedar, larch
38
What are some examples of manufactured board?
Plywood, marine plywood, aeroply, chipboard, MDF
39
What’s a thermoplastic?
A material that can be repeatedly reheated and reshaped, allowing it to be recycled
- have longer linear chain molecules
40
What’s a thermosetting polymer?
A material that when heated undergoes a chemical change, whereby the molecules form rigid cross links
Can’t be reshaped and reheated
41
What’s an elastomer?
A material which at room temperature can be deformed under pressure then upon release, will return to its original shape
- have weak bonds that allow them to stretch
42
What are some examples of thermoplastics?
- low density polyethylene (LDPE)
- High density polyethylene (HDPE)
- polypropylene (PP)
- high impact polystyrene (HIPS)
- acrylonitrile butadiene styrene (ABS)
- polymethyl methacrylate (PMMA)
- polyethylene terephthalate (PET)
- nylon
- PVC
43
What are some examples of thermosetting polymers?
- urea formaldehyde (UF)
- melamine formaldehyde (MF)
- polyester resin
- epoxy resin
44
What are some examples of elastomers?
- natural rubber
- polybutadiene
- neoprene
- silicone
45
What are some examples of papers and boards?
-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
46
What is a composite?
A material comprised of two or more different materials, resulting in a material with enhanced properties
47
What are some examples of composites?
- carbon fibre reinforced plastic (CFRP)
- glass fibre reinforced plastic (GRP)
- tudsten carbide
- aluminium composite board
- concrete
- fibre cement
- engineered wood
48
What’s a smart material?
A material whose physical properties change in response to an input or change in the environment
49
What are some examples of a smart material?
- shape memory alloys (SMA)
- thermochromatic pigment
- phosphorescent pigment
- photochromic pigment
50
What’s a modern material?
A material developed through the invention of new or improved processes
- they aren’t smart as they don’t react to external change
51
What are some examples of modern materials?
- Kevlar
- precious metal clay (PMC)
- high density modelling foam, polymorph
52
What’s the simple workshop test for toughness?
Place the material in a vice and hit it with a hammer
Tough materials will absorb the impact and brittle materials will bend or shatter
53
What’s the simple workshop test for hardness?
The material is tested using a dot punch and the force of the hammer, then look at the size of the indent produced
54
What’s the simple workshop test for malleability and ductility?
Sample material placed in a vice and bent at 90º
- cracks on the outside indicate a lack of ductility
- cracks on the inside indicate a lack of malleability
55
What’s the simple workshop test for tensile strength?
The material is clamped then force is gradually put on it, and the extension is measured
56
How do you test for corrosion?
- place equal size material samples outside in an area exposed to the effects of weather and leave for a set length of time
- materials can then be visually inspected for surface corrosion
57
How do you test for electrical conductivity?
- collect material samples of the same dimension and mark a set distance to place the multimeter probes
- Measure the resistance on the multimeter
- the higher the resistance, the lower the conductivity
58
What’s the test for thermal conductivity?
- collect material samples of the same dimensions
- measure a set distance from one end of the material and place a thermometer there
- light a Bunsen burner under the other end of the material
- record the time it takes for the temperature to reach the set point at the other end of the material
- the shorter the time it takes, the higher the thermal conductivity of the material
59
What’s the difference between simple workshop tests and industrial tests?
Simple workshop tests use basic tools and equipment, when industrial test are usually carried out in labs with specific testing machinery, using standardised test pieces of materials
60
What is the industrial test for tensile strength?
- using a tensometer machine
- the standard test piece is held in a clamp at each end
- one clamp is fixed and the other moves on a worm drive gear mechanism, putting the material under tension
- the test material is stretched, the load and distance travelled is plotted, giving information on the elastic limit, yield point, maximum load and final breaking point after ‘necking’
61
What is the industrial test for toughness?
- the izon impact test
- a notched test piece is held vertically in the vice of the machine
- a pendulum is released from a set position and swings to strike the seat piece
- the energy absorbed by the test piece is calculated from the height the pendulum swings to after it hits the test piece
- the material that absorbs the most impact is the toughest and gives the les pendulum swing
- brittle material absorbs less energy and the pendulum swings further
62
What is the industrial test for toughness?
- the izon impact test
- a notched test piece is held vertically in the vice of the machine
- a pendulum is released from a set position and swings to strike the seat piece
- the energy absorbed by the test piece is calculated from the height the pendulum swings to after it hits the test piece
- the material that absorbs the most impact is the toughest and gives the les pendulum swing
- brittle material absorbs less energy and the pendulum swings further
63
What are the 3 types of industrial tests used to test the hardness of a material?
What do they all involve?
- Rockwell test
- brinell test
- vickers pyramid test
All involve a load being applied to a material with the resultant indentation determining the hardness of the material
- the smaller the indentation the harder the material
64
What is the industrial test on the hardness of a product?
What are the 2 standard methods?
Non-destructive testing (NDT)
- used to find defects in the material of a product
1. Ultrasonic – sound waves are pulsed into the material, different sounds indicate faults
2. X-ray – an x-ray beam passes through the material and an image is projected on to a display screen, allowing the observation of tiny details such as a hairline crack in the material
65
What is the Rockwell test?
One of the tests for hardness
• preload applied to the material sample using a diamond indenter, which breaks through just the surface of the material
• diamond is used so that it doesn’t deform under load
• preload is the datum or zero reference position
• an additional load is then applied to the test material and held for a predetermined length of time (dwell time)
• the load is released and the distance between the preload and the applied load is measured
66
What is the brinell test?
A test for hardness
• a hardened standard size steel ball is forced into the materials surface using a pre-set load
• the diameter of the indent in the surface is measured
67
What is the vickers pyramid test?
A test for hardness
• used for very hard materials
• uses a diamond square-based pyramid to indent the surface of the material
• a microscope is used to measure the size of the indent
68
What is the industrial test for malleability and ductility?
Band test
- tests how well a material withstands cracking during one continuous bend
•the test piece is placed into a bending machine and held, supported at the ends
•a mandrel or plunger loads the test piece at the centre and bends it to a predetermined angle or until the test piece fractures. The material is then inspected
• cracks on the outer bend indicate the level ductility.
- a ductile material will have a lot of plastic deformation prior to failure
• cracks on the inside of the bend will indicate the level of malleability
69
What’s the industrial test for corrosion?
Material samples of equal size would be placed into the simulated weather environment and left for a set length of time
Materials can then be inspected foe surface surface corrosion
70
What’s the industrial test for electrical conductivity?
Collect material samples of the same dimensions
- on the top surface, mark a set distance at each end
- place a multimeter probe on each mark
- measure the resistance
- the higher the resistance, the lower the conductivity
71
What’s the industrial test for thermal conductivity?
- a square shaped material test piece is placed between two temperature controlled plates
- the temperature is increased at a controlled rate and the heat flow through the material is measured by the heat flow sensors placed on the surface of the material.
- as the material is heated to a specific temperature, the sensors measure and record the rate of thermal conductivity
72
What is paper thickness measured in?
Grams per square metre (gsm)
73
What re 6 different types of paper?
- layout paper
- bleed proof paper
- treated paper
- cartridge paper
- partridge paper
- water colour paper
74
What are what are 6 types of card/board?
- corrugated card
- duplex card
- mount board
- bleached card
- foil back and laminated card
- metal effect card
75
What is moulded paper pulp?
Recycled paper pulp moulded when wet and dried to a specific shape
76
What are the characteristics of treated paper?
Plain paper with a clear binder or dye layer applied to help hold the image on the paper surface
77
What are the characteristics of mount board?
Made form compressed cotton fibres to produce a rigid board
78
What are the characteristics of bleached card?
Chemically treated to brighten the surface to make it suitable for high-quality printing
79
What is a compliment material?
A material that can be scored, folded and cut with basic tooling to form items such as nets for packaging
80
What is foil-backed and laminated card?
Card with polymer film or foil applied to provide a water-resistant/heat insulating layer
81
What is metal effect card?
High-quality card, often used for gift boxes, which has a thin metal-effect layer applied to the outer surface for enhanced aesthetics
82
What are 8 types of polymer-based sheet and films?
- foam board
- fluted PP sheet
- styrofoam
- low density polyethylene (LDPE) sheet
- plastazote foam
- cellulose acetate
- polylactide
