DT terms

Question 1

Mechanical

Answer 1

Reacting to physical properties –working properties

Question 2

Electrical

Answer 2

Resistance or aid of electrical flow

Question 3

Chemical

Answer 3

Reaction with other chemicals

Question 4

Thermal

Answer 4

Reaction, resistance or aid of heat

Question 5

Magnetic

Answer 5

Attraction to magnetic force (usually ferrous metals)

Question 6

Permeability

Answer 6

Degree of permeability (passing through)

Question 7

Aesthetic

Answer 7

Visual property

Question 8

Tactile

Answer 8

Touch, or feel of material

Question 9

Strength

Answer 9

Ability to withstand force without being deformed or broken

Question 10

Hardness

Answer 10

Ability to withstand abrasive wear (indenting/scratching)

Question 11

Toughness

Answer 11

Ability to withstand impact/bending

Question 12

Durability

Answer 12

Ability to withstand general wear and tear, along with corrosion and weathering

Question 13

Elasticity

Answer 13

Ability to flex and return to original shape after removal of force

Question 14

Plasticity

Answer 14

Ability to permanently change shape by external force without damage

Question 15

Malleability

Answer 15

Ability to be deformed by compression

Question 16

Ductility

Answer 16

Ability to be stretched/drawn out

Question 17

Tensile strength

Answer 17

Ability to withstand stretch/pull

Question 18

Compressive strength

Answer 18

Ability to withstand crushing/pushing

Question 19

Bending strength

Answer 19

Ability to withstand bending

Question 20

Shear strength

Answer 20

Ability to withstand sliding forces

Question 21

Torsional strength

Answer 21

Ability to withstand twisting

Question 22

Traditional materials

Answer 22

Used for centuries (wood, metal)

Question 23

Modern materials

Answer 23

Materials developed in the last century

Question 24

Smart materials

Answer 24

Change physical properties depending on external factors

(SMA, SMP, smart pigment, thermochromic pigment, photochromic pigment, phosphorescent pigment, smart grease, polymorph)

Question 25

Thermoplastic (poly...)

Answer 25

Plastics that can be repeatedly reheated/remoulded

Question 26

Thermosets (resin/formaldehyde)

Answer 26

Chemically reacts when heated to prevent remoulding/reheating

Question 27

Elastomers

Answer 27

Can be distorted but will return to original shape

Question 28

Plastic advantages

Answer 28

1. strength-to-weight ratio 2. good insulators 3. lightweight 4. resistant to corrosion/weathering

Question 29

Bioplastics (e.g. PLA)

Answer 29

Biodegradable plastics

Question 30

Softwood

Answer 30

From coniferous trees (needle leaves, all year round) e.g. pine, fir, spruce

Question 31

Hardwood

Answer 31

From deciduous trees (broad leaves, shed in autumn) e.g. oak, ash, mahogany, teak

Question 32

Manufactured board

Answer 32

Made from wood pulp, chips, layers

Question 33

Quarter saw wood

Answer 33

Saw in blocks - expensive and wasteful, but aesthetically pleasing

Question 34

Through and through sawing

Answer 34

Tangentially sawing - cheap and less wasteful, but prone to distortion

Question 35

Chipboard

Answer 35

Compressed actual wood chips

Question 36

Conti board

Answer 36

Laminated chipboard

Question 37

MDF

Answer 37

Compressed wood grains

Question 38

Veneers

Answer 38

Thin pieces of wood to laminate

Question 39

Plywood

Answer 39

Veneers stuck together

Question 40

Blockboard

Answer 40

Softwood strips with veneers

Question 41

Hardboard

Answer 41

Smooth and hard sides together, compressed wood grains

Question 42

Composites

Answer 42

A mixture of materials combined to enhance their individual properties.

Question 43

Types of fibre-based composite

Answer 43

Glass fibre, Carbon Fibre Reinforced Polymer, Kevlar

Question 44

Glass fibre

Answer 44

Glass spun into fibre, coated in aid bonding to polyester resin Used in instrument casing, boats

Question 45

CFRP

Answer 45

Carbon Fibre Reinforced Polymer Woven to matt, then impregnated with resin and baked at 170C Used in F1 car bodies, racquets, performance equipment

Question 46

Kevlar

Answer 46

Chemical resistant, cut resistant, and flame resistant, five times stronger yet half the weight of steel Made from aromatic and nylon-like particles added together

Question 47

Ferrous metals

Answer 47

Metals containing iron and carbon

Question 48

Non-ferrous metals

Answer 48

Metals that do not contain iron and carbon

Question 49

Alloys

Answer 49

Combination of metals to enhance their properties

Question 50

Cast iron

Answer 50

Liquefied pig iron 3.5% carbon/silica Brittle, requires heat treatment to become malleable Casings, pans

Question 51

Mild steel (BDMS)

Answer 51

Bright Drawn Mild Steel 0.15-0.3% carbon Car bodies, hinges

Question 52

Medium carbon steel

Answer 52

0.3-0.7% carbon Springs, general gardening tools

Question 53

High carbon steel

Answer 53

0.7-1.7% carbon tools, drill bits, blades

Question 54

Alloys

Answer 54

A mixture of metals combined to improve their properties

Question 55

Stainless steel

Answer 55

Ferrous alloy Highly resistant to corrosion, hygienic, wear resistant kitchenware, sinks

Question 56

Brass

Answer 56

35% copper and zinc resistant to corrosion, conductive valves, taps

Question 57

Bronze

Answer 57

10% copper and tin expensive due to copper coins, statues, bearings

Question 58

Duralamin

Answer 58

Aluminium with 4% copper, 1% manganese, 0.1% magnesium stronger and lighter than aluminium

Question 59

Pewter

Answer 59

Tin with copper, antimony easily melts, cheap picture frames, cups, models, metallic gifts/charms