Manufacturing - 1.2 Materials Flashcards
Woods are split up into two groups, what are they?
Natural woods: wood that natural come from trees
Manufactured boards: wood that has been cut up and glued back together in a factory.
What is the preparation of wood?
- Felling: cutting down trees
- Conversion: sawing up a tree into boards or planks. Done by radial or plain sawing.
- Seasoning: drying moisture out of the wood either naturally or by kiln ( a big oven used to dry moisture out of wood).
Natural woods are split up into what 2 different groups?
Softwoods: Come from coniferous trees; evergreens grown in cooler climates.
Hardwoods: come from deciduous trees- those that shed their leaves in winter. Grown in hot climates.
What are examples of softwoods and what are their properties?
Examples of softwoods: pine, redwood, spruce, cedar.
Properties of softwoods: light coloured, easily shaped, hard/ durable, uses include roof trusses, pallets, attic beams, furniture.
What are examples of hardwoods and their properties?
Examples of hardwoods: Mahogany, Beech, Ash, Oak.
Properties of hardwoods: Reddish brown, strong, expensive, hard/durable, used for furniture/doors.
What are manufactured boards?
Manufactured boards are made by cutting up natural woods and putting them back together in different ways. Unlike natural woods, they are cheap and can come in large sizes.
What are examples of manufactured boards?
Plywood: Made up from several thin layers of wood (veneers) which are stuck at right angles to each other for extra strength.
MDF-Medium Density Fibreboard: smooth, strong hardboard that takes paint well. It is commonly used in furniture with an outer veneer.
Chipboard: Made From small chips of wood that are mixed with glue and squeezed together. Weak material can be strengthened with a veneer but when wet it is weak.
Blackboard: Made from lengths of solid wood sandwiched between 2 thin veneers. Very strong material used for platforms/stages.
What are plastics made from and what are their 2 groups?
Plastics come from crude oil. Their 2 main groups are:
Thermoplastics: can be heated and re-shaped over and over. Can be re-cycled.
Thermosetting plastics: when heated and re-shaped they stay that way. Can only be formed into shape once. Can’t be recycled.
What are examples of thermoplastics?
Acrylic: Perspex, shatterproof and can be transparent/opaque. Easily scratched and quite brittle, used for signs/display units.
Polystyrene: different forms; Expanded polystyrene is soft and a very good heat insulator and shock absorber(packaging); Rigid polystyrene is brittle (plastic cutlery and light casing).
ABS:(acrylonitrile-butadiene-styrene) used for PC/TV casings, telephones, keyboards, etc.
Nylon: Fibre-based plastic that is used for clothing products, small gears in clock, etc.
What are examples of thermosetting plastics?
Melamine: very good thermal, electrical insulator, it is used on laminated worktops and drawer handles.
Urea formaldehyde: Hard And colourless. It can be dyed and is used for a range of products: knobs, handles, electrical fittings.
Epoxy Resin: A type of glue which, when mixed with a chemical, becomes very strong. It can bond different types of material.
Polyester Resin: A type of glue which is mixed with: -glass to form fibreglass or -carbon to form carbon fibre (2 extremely light and strong compound materials).
What are metals, what are their 2 groups and what is an alloy?
Some metals are extracted in their natural state and some are combined to make an alloy. The two groups of metals are;
Ferrous: those which contain iron and rust.
Non-ferrous: those which do not contain iron and do not rust.
Alloy: a mixture of 2 or more metals to obtain a desirable property.
What are examples of ferrous metals?
Mild steel: Iron + 0.5% carbon, cheap, easy to work with. Uses are nuts+bolts, table frames,chairs,etc.
High carbon steel: Iron + 1% carbon. Very hard, used for drill bits & cutting tools.
Stainless steel: steel + chronium alloy- doesn’t rust. Used for kitchen sinks, cutlery.
What are examples of non-ferrous metals?
Aluminium: light + strong, abundant, easy to use. Used for ladders, coke cans, aeroplanes.
Copper: excellent conductor, can be drawn into a wire easily (ductile). Used for electrical wires, plumbing pipes, radiators.
Brass: copper/zinc alloy, decorative. Used for musical instruments, keys, door handles, etc.
What is Graphene?
A carbon based material with a hexagonal atomic structure. Strongest material on earth- X200 times stronger than steel. Thinnest material on earth- considered to be 2 dimensional.
- Most conductive material on earth- better than copper.
- Flexible
- Possible future uses: mobile/screen technology, batteries, electric cars, solar technology, water filtration.
