Core Content 1 Flashcards
Name three properties of a ferrous metal
Contain iron
Rust
Magnetic
Give three examples of ferrous metals and a property for each
Mild steel - strong
Stainless steel - lightweight
Cast iron - durable
Describe three properties of non-ferrous metals
Doesn’t contain iron
Doesn’t rust
Usually not magnetic
Give three examples of non ferrous metals and their properties
Aluminium
Copper
Tin
All conductors
Define an alloy
Metal that is mixed or combined together with another substance to improve its qualities
(E.g. stronger, harder, lighter, rust resistant)
Give three examples of alloy eagles and what they are made from
Brass = copper zinc Bronze = copper tin Pewter = tin antimony copper
Define a polymer
Very large chain like molecule made up of monomers
Name the two types of polymers
Thermo polymers
Thermosetting polymers
Give some properties of thermo polymers
Soften when heated Can be moulded Harden once cooled Can be reheated Good plastic memory
Give three examples of examples of thermo polymers and their properties
PET = strong, water proof Acrylic = brittle but hard ABS = impact resistant, easy to clean
Give some properties of thermo setting polymers
Chemical change when heated
Become hard when cooled
Can’t be reheated
Bad plastic memory
Give three examples of thermosetting polymers and their properties
Silicone = insulator, durable
Polyester resin = strong, waterproof
Epoxy resin = strong, cheap
Describe woven fabrics and give some examples
Made on manual automated looms Warp and weft yarns Warp = vertical Weft = horizontal Corduroy, cotton, satin
Describe non-woven fabrics and give some examples
Lack strength
Bonded using pressure and heat or adhesives
Lose strength once wet
Felted fabric = heated, added moisture, friction
Used for surgical masks/gowns, wet wipes, tea bags, nappies
What is glass reinforced plastic and what is it used for
Polyester resin with fibre glass
Like a polymer but stronger
Used for boats and car bodies
What is carbon fibre and what’s it used for
Polyester resin with carbon fibres
Even stronger and lightweight that GRP
Used for helmets and bikes
What is Kevlar and what is it used for
Plastic woven in
Stronger and lighter than carbon fibre
Used for bulletproof vests
What are laminates and what are they used for
Layers of different materials
Improve strength, durability and water resistance, warp resistant, cheaper than timber, bigger boards
Used for waterproof jackets
Name 5 types of paper
Layout, copier, cartridge, bleedproof, sugar
Properties and uses of card
180-300gsm, wide range of colours/finishes/sizes, thin easy to fold/cut/print
Greetings cards
Properties and uses of cardboard
300 microns+, inexpensive, easily printed on, different sizes/surfaces/finishes
Cereal boxes, sandwich packets
Properties and uses of corrugated cardboard
3000 microns+, strong, lightweight, hard to bend, insulating
Pizza boxes
Properties and uses of board sheet
1400+ microns, rigid, smooth, different colours
Picture frame mounts, architectural modelling
Give three examples of laminated layers
Foam board
Styrofoam
Corriflute
Properties and uses of foam board
5000 microns, lightweight, range of colours/sizes/thicknesses, rigid, insulating
Modelling
Properties and uses of styrofoam
Range of sizes/thickness, string, lightweight, water resistant, insulator
Wall insulation
Properties and uses of corriflute
Range of colours/sizes, rigid, lightweight, waterproof
Signs, packaging
Name three types of wood
Hardwoods
Softwoods
Manufactured boards
Properties and examples of hardwood
Deciduous trees, expensive, more durable, finishes well
Oak, mahogany, beech, ash
Properties and examples of softwoods
Coniferous trees, cheaper, less durable/strong, quicker to grow
Pine, cedar, spruce
Properties and examples of manufactured boards
Layered sheets of soft and hard woods
Plywood, MDF, chipboard, block board
Names four types of fibres
Natural fibres
Synthetic fibres
Mixed fibres
Blended fibres
Properties and examples of natural fibres
Found and sourced from plants and animals
Cotton, wool, silk
Properties and examples of synthetic materials
Man made from petrochemicals
Polyester, acrylic, nylon
Properties of mixed and blended fibres
Yarns of different fibres added together during production, mixed for aesthetics (lustre, colour)
Mixed/blended fabric example
Poly cotton
Polyester and cotton, strength, breathability, absorbency, crease resistance, cheaper
Properties of knitted fabrics
Rows of interlocking loops/stitches
Weft- horizontal
Warp- vertical
Properties of polymorph
Polymer granules, 60°c water, melted, can be moulded, reheat using water/hairdryer
Properties of Teflon
Non-stick coating, paints, cookware, carpets
Properties of Lenticular plastic sheet
Smooth on one side, small lenses on the other, 2D image, visual illusions
Properties of flexiply
Plywood, very flexible/bendable
Properties of precious metal clay
99% gold/silver, 1% clay, shaped at room temperature, kiln to harden
Used to make jewellery
Properties of conductive polymers
Plastic that conducts electricity
Properties of shape memory alloy
Remembers original shape when deformed, returns when heated, spectacle frames, cooling vents
Properties of shape memory polymers
Programmed to remember original shape when heated
Properties of thermochromic sheet
Liquid Crystal ink, changes colours above 27°c
Toys, jewellery, temperature indicators
Properties of thermochromic pigments
Novelty mugs, reveal design when heat is added
Add to polymers, plastics react to heat, drink stirrers, baby sooons, temperature warning/indicator
Properties of photochromic materials
React to light, spectacles, turn dark in bright sun
Properties of self healing materials
Detract and repair damage done, embedded capsules, release adhesives
Bio concrete, bacteria reacts with water to form limestone
Properties and uses of nomex
Heat/flame resistant
Racing driver/firemen/astronaut clothing
Oven gloves
Fire resistant insulation
Properties and uses of Kevlar
Resistant to abrasion, sharp objects Stab/bullet proof vests, police/armed forces Motorcycles clothing Tyres Butcher/fishmonger gloves
Properties and uses of coolmax
Wicks water away from body, increase breathability
Bedding, sportswear, uniforms, underwear
Properties and uses of fastskin
Mimics shark skin, streamlining in water
Sportswear/swimwear
Density
g/cm3 = mass/volume
Metals denser than styrofoam
Strength/tenacity
Ability to withstand forces
Compressive: withstand compression
Tensile: withstand tension
Yield: withstand forces before being permanently changed
Impact: withstand sudden forces
Composite materials, high tensile, low compressive
Hardness
Resistant to pressure
Scratch, indentation, rebound
Carbon steel
Usually high hardness = high brittleness
Durability
Ability to withstand wear/damage
Strength to weight ratio:
Strength compared to weight
High ratio = strong but lightweight (aircrafts, carbon/glass fibre, polymers)
Stiffness
Rigidity
Ceramics, glass, steel, high rigidity
Polymers, foam, rubber, low rigidity
Elasticity
Ability to return to original shape after extension force
Elastic band
Impact resistance
Ability to withstand shock applied over a short time period
Polymers, rubber, nylon, mild steel (softer metal)
Plasticity
Ability to permanently change shape whe force is applied
Sheet steel
Ductility and malleability
Examples
Conditions that change it
D- How easy it is to deform without breaking M- When rolled into a sheet Soft metals (lead), polymers Temperature and application change properties
Brittleness
How easily a material breaks when bent or impacted
Shatter/break rather than bend
Opposite of ductility
Decrease temperature, increase brittleness
Metals (iron/aluminium)
Corrosive resistance
Susceptibility to degradation from the elements
Rust- ferrous metals, oxygen and moisture
Timber- hardwood, resistant, softwood, rot
Polymer- UV light, oxygen and chlorine, swell/break
Water resistance
Ability to resist ingress of water
Polymers (rubber, PVC)
Coat other materials (clothing, boats, footballs)
Absorbency
Ability to absorb moisture
Cotton, linen, wool, cardboard
Flammability
Ability to burn/ignite
Timbers, polymers, fabrics, papers, boards
Metals not flammable
Electrical conductivity + examples
How easy it is for electricity to flow through
Metals- good
Wood/rubber- bad
Magnetic properties
Forces attract/repulse each other
Metals containing iron/nickel/cobalt/magnetite
Ferro-magnetic, artificial magnetism, fades over time
Thermal conductivity
Thermal fabrics, acrylic, viscose, jackets, cool bags, ironing boards
Metals, good, used in radiators
Heat resistance- styrofoam, softwoods, porous materials