Technical Principles Flashcards
Materials, Manufacture, H&S, Design processes (73 cards)
Classifications of material properties
Mechanical:
compressive strength, tensile strength, hardness, toughness, ductility, malleability
Physical:
electrical properties, thermal properties, aesthetics
Groups of materials
Metals, woods, polymers, papers and boards, smart materials, modern materials
Types of metals
Ferrous, non-ferrous, alloy
Ferrous metals
A metal containing iron and carbon - Mild Steel – Strong, tough, rusts easily, used in car bodies, construction.
Stainless Steel – Corrosion-resistant, tough, used in cutlery & sinks.
Cast Iron – Hard but brittle, used in vices & engine blocks.
Non-ferrous metals
Does not contain iron
Aluminium – Lightweight, corrosion-resistant, used in drink cans, aircraft.
Copper – Conducts electricity & heat, used in wiring & pipes.
Brass (Alloy: Copper + Zinc) – Corrosion-resistant, used in musical instruments.
Alloys
A metal made from 2 or more metals - stainless steel, bronze
Types of woods
Hardwood, softwood, manufactured board
Hardwood
Wood from deciduous trees - lose leaves
Oak – Tough, durable, attractive grain, used in furniture & flooring.
Mahogany – Easy to work, durable, used for high-end furniture.
Beech – Tough, doesn’t splinter, used for toys, tools & furniture.
Ash – Flexible, tough, used in tool handles & sports equipment.
Softwood
Wood from coniferous trees
Pine – Lightweight, easy to work, used for construction & furniture.
Cedar – Resistant to weather & insects, used for outdoor buildings.
Manufactured board
Man-made wood based composite - Plywood – Strong, stable, used in furniture, construction.
MDF (Medium Density Fibreboard) – Smooth, easy to finish, used in furniture.
Chipboard – Cheap, weak unless laminated, used in flat-pack furniture.
Types of polymers
Thermoplastic, thermosetting polymer, elastomer
Thermoplastic
Can be repeatedly heated and reformed and has long linear chain molecules with Van Der Walls forces - Acrylic (PMMA) – Hard, brittle, used in signage & car lights.
Polyethylene (LDPE/HDPE) – Flexible (LDPE) or strong (HDPE), used in bottles & bags.
Polypropylene (PP) – Tough, flexible, used in food containers & chairs.
Polyvinyl Chloride (PVC) – Hard (rigid) or flexible, used in pipes & raincoats.
Thermosetting polymer
When heated, undergoes a chemical change where molecules form rigid cross links
Epoxy Resin – Strong, durable, used in adhesives & electronics.
Melamine Formaldehyde – Heat-resistant, used in kitchen worktops.
Urea Formaldehyde – Hard, electrical insulator, used in plug sockets.
Elastomer
At room temperature can deform and return to its original shape - rubber, silicone
Composites
Material composed of two or more different materials
Carbon Fibre Reinforced Polymer (CFRP) – Lightweight, strong, used in sports equipment & cars.
Glass Fibre Reinforced Polymer (GRP) – Tough, corrosion-resistant, used in boats.
Concrete – Strong in compression, used in buildings.
Smart materials
Physical properties engage in response to and environmental stimuli
Thermochromic Pigments – Change color with heat (used in mugs, forehead thermometers).
Photochromic Pigments – Change color with UV light (used in sunglasses).
Piezoelectric Materials – Generate electricity when deformed (used in sensors).
Modern materials
Material developed through the invention of new or improved processes
Shape Memory Alloy (SMA/Nitinol) – Returns to original shape when heated (used in braces).
Types of papers (to be familiar with)
Layout paper, cartridge paper, tracing paper, bleed proof paper, treated paper, watercolour paper, corrugated card, bleached card, mount board, duplex card, foil backed, metal effect, moulded paper pulp
Polymer based sheets
Foam board, fluted polypropylene (signs), LDPE sheets (bags), polyactide sheet (biodegradable)
Softwoods to know
People - Pine - construction
Sometimes - Spruce - furniture
Don’t - Douglas - construction
Read - Redwood - (Pine)
Letters - Larch - garden furniture
Carefully - Cedar - sheds
Hardwoods to know
On - Oak - Furniture
A - Ash - Tool handle
Mountain - Mahogany - Indoor furniture
They - Teak - Outdoor furniture
Built - Birch - Furniture
Bridges - Beech - Chairs
Manufactured boards to know
Plywood - desks
Marine plywood
Aeroply
Flexible plywood
Chipboard
MDF
Polymers to know
Thermoplastics - change
LDPE
HDPE
PP
HIPS
ABS
PMMA
Nylon
PVC
PET
Thermosets
UF
MF
Elastomers to know
Natural rubber
Polybutadiene
Neoprene
Silicone
TPE