Materials Flashcards
Define wood
Wood is a porous and fibrous structural tissue found in the stems and roots of trees and other woody plants
What are the wood subcategories
Hard woods
Soft woods
Manufactured boards
What are the advantages of using wood
- Strong and reasonably lightweight
- Versatile, can be put to many uses
- Easy to work with
- A sustainable resource if managed properly
What are the disadvantages of using wood?
- Many degrade and rot if wet
- Flammable
- Logging and manufacture can deplete forests
- Wood can swell and shrink
What are hardwoods
Hardwoods come from deciduous or broad-leafed trees. They are generally slow growing which tends to make them harder and more expensive. Please note though that not all hardwoods are hard, Balsa which is very soft and is often used for model planes is in fact a hardwood. Hardwoods are sold by the cubic metre then this is sawn to the size the customer requires. Some timber is machined into many sections called mouldings for example, dowel, beading, etc.
Name 5 types of hardwood
Beech
Oak
Mahogany
Teak
Balsa
Describe beech (hardwood)
A straight-grained hardwood with a fine texture. Light in colour. Very hard so is ideal to be used where it is being bashed around and used often. Beech is also very easy to work with.
Describe Oak
A very strong wood which is light in colour. Open grain. Hard to work with. When treated it looks very classy and elegant. A hardwood.
Describe Mahogany
An easy to work wood which is reddish brown in colour. This wood is very expensive. A hardwood.
Describe Teak
A very durable oily wood which is golden brown in colour. Highly resistant to moisture and outdoor weather. A hardwood
Describe Balsa
is a pale white to gray. It has a distinct velvety feel. It has exceptional strength to weight properties. It is the lightest and softest wood on the market. A hardwood.
Describe the uses of beech
Used for furniture, toys, tool handles. Can be steam bent.
Describe the uses of oak
Used for high class furniture, boats, beams used in buildings, veneers.
Describe the uses of mahogany
Used for expensive indoor furniture, shop fittings, bars, veneers.
Describe the uses of teak
Used for outdoor furniture, boat building, laboratory furniture and equipment.
Describe the uses of balsa
Used for light work such as model making and model airplane construction
Describe Softwoods
Softwoods come from coniferous trees which have needles instead of leaves. Softwoods grow faster than hardwoods and so are cheaper they are also easier to work with as they are softer than hardwoods. These are supplied in standard sections sawn and planned smooth. Softwood sizes are confusing because they are smaller once they are planned.
Name 4 types of softwoods
Scots pine
Spruce
Yellow Cedar
European redwood
Describe Scots pine
A straight-grained softwood but knotty. Light in colour. Fairly strong but easy to work with. Cheap and readily available. A softwood.
Describe spruce
Creamy-white softwood with small hard knots. Not very durable. A softwood.
Describe yellow cedar
A pale yellow-coloured softwood with a fine even texture. Light in weight but stiff and stable.
Describe European redwood
Quite strong, Lots of knots, durable when preserved. cheap. A softwood
Describe the uses of Scots pine
Used for DIY and cheap quality furniture. Mainly used for constructional work and simple joinery.
Describe the uses of spruce
Used for general indoor work, whitewood furniture used in bedrooms and kitchens
Describe the uses of yellow cedar
Used for furniture, boat building, veneers, and model making.
Describe the uses of European Redwood
Used for general woodwork, cupboards, shelves, roofs.
What are manufactured boards?
Manufactured boards are timber sheets which are produced by gluing wood layers or wood fibres together. Manufactured boards often make use of waste wood materials. Manufactured boards have been developed mainly for industrial production as they can be made in very large sheets of consistent quality. Boards are available in many thicknesses.
Name 5 types of manufactured boards
MDF
plywood
Chipboard
Blockboard
Hardboard
Describe MDF
Smooth, even surface. Easily machined and painted or stained. Also available in water and fire resistant forms. A manufactured board.
Describe Plywood
A very strong board which is constructed of layers of veneer or piles which are glued at 90 degrees to each other. Interior and exterior grades are available. A manufactured board.
Describe chipboard
Made from chips of wood glued together. Usually veneered or covered in plastic laminate. A manufactured board
Describe blockboard
Similar to plywood but the central layer is made from strips of timber. Good for shelves and worktops. A manufactured board.
Describe hardboard
A very cheap particle board which sometimes has a laminated plastic surface. A manufactured board.
Describe the uses of MDF
Used mainly for furniture and interior panelling due to its easy machining qualities. Often veneered or painted.
Describe the uses of plywood
Used for strong structural panelling board used in building construction. Furniture making. Some grades used for boat building and exterior work
Describe the uses of chipboard
Used for kitchen and bedroom furniture usually veneered or covered with a plastic laminated. Shelving and general DIY work.
Describe the uses of blockboard
Used where heavier structures are needed. Common for shelving and worktops.
Describe the uses of hardboard
Used for furniture backs, covering curved structures, door panels.
What are metals?
Metals are made by mining ore from within the earth. Metal is then extracted out of the rocks in an extremely large scale industrial process.
What are the 3 main types of metals
There are three main types of metals ferrous metals, non ferrous metals and alloys
What are ferrous metals?
Ferrous metals are metals that consist mostly of iron and small amounts of other elements. Ferrous metals are prone to rusting if exposed to moisture. Ferrous metals can also be picked up by a magnet. The rusting and magnetic properties in ferrous metals are both down due to the iron. Typical ferrous metals include mild steel, cast iron and steel.
What are non ferrous metals?
Non-ferrous metals are metals that do not have any iron in them at all. This means that Non-ferrous metals are not attracted to a magnet and they also do not rust in the same way when exposed to moisture. Typical Non-ferrous metals include copper, aluminium (coke cans), tin and zinc
What are metal alloys?
Alloys are substances that contain two or more different metals and occasionally other elements. The metals are carefully chosen and mixed to achieve specific properties these include reducing the melting point making the alloy light weight, etc
What are the advantages of using metals
- Very strong
- Easily recyclable
- Excellent conductors of heat and electricity
- Able to be shaped into many forms
What are the disadvantages of using metals
- A finite resource. Once mined they can’t be replaced
- Ferrous metals rust and corrode
- Some metal finishes can tarnish over time
- Difficult and expensive to work with
Name 5 types of ferrous metals
Cast Iron
Mild steel
High carbon steel
Stainless steel
Iron
What are the properties of cast iron
Strong, tough, cannot be bent
What are the properties of mild steel
Ductile and malleable yet tough. Easy to weld
What are the properties of high carbon steel
Brittle, difficult to cut, resistant to wear
What are the properties of stainless steel
Corrosion resistant, tough, difficult to cut and shape
What are the properties of iron
Strong, tough, cannot be bent
What are the identifying features of cast iron
Dark grey/black
Usually painted to prevent rust
What are the identifying features of high carbon steel
Silvery grey with poor corrosion resistance
What are the identifying features of mild steel
Silvery grey with poor corrosion resistance
What are the identifying features of stainless steel
Silvery grey. Can be dull or very shiny
What are the identifying features of iron
Dark grey/black
Usually painted to prevent rust
What are some common uses of cast iron
Baths, garden furniture, pots
What are some common uses of mild steel
Car bodies, nuts, bolts, nails, wire fencing
What are some common uses of high carbon steel
Tools: saw blades, files, screwdrivers, chisles,etc
What are some common uses of stainless steel
Sinks, cutlery, saucepans, lighting, bikes
What are some common uses of iron
Baths, garden furniture, pots
Name 3 non ferrous metals
Brass
Copper
Aluminum
What are the properties of Aluminium
Light and strong. Malleable, conducts heat and electricty. Corrosion resistant
What are the properties of Brass
Rigid, polishes well. Conducts heat and electricity well. Solders well
What are the properties of Copper
Tough, ductile, malleable. Excellent conductor of electricity and heat. Solders well
What are the identifying features of aluminium
Shiny silvery grey
What are the identifying features of brass
Golden and polishes well
What are the identifying features of copper
Deep orange-brown colour. Corrodes to a green-blue
What are some common uses of aluminium?
Kitchen foil, drinks cans, boat hulls, lightweight equipment
What are some common uses of brass
Taps, plaques, ornaments, instruments
What are some common uses of copper
Wires, pipes, circuit boards, roofing and cladding
Describe plastics
Plastics are the most widely used material in commercial production. Plastics can be created from two main sources which are natural and synthetic materials.
What are the 2 main groups of plastics?
There are two main groups of plastic which are thermosetting plastics and thermoplastics.
What are thermoplastics
Thermoplastics can be heated and shaped many times. Thermoplastics will soften when it is heated and can be shaped when hot. The plastic will harden when cooled, but can be reshaped because their is no links between the polymer chains.
What are thermosetting plastics
Thermosetting plastics can only be heated and shaped once. If re-heated they cannot soften as polymer chains are interlinked. Separate polymers are joined in order to form a huge polymer.
What are the advantages of using plastics
- Strong and lightweight
- Coloured and/or transparent
- Very versatile, many uses.
- Easily shaped and moulded
What are the disadvantages of using plastics
- Some are brittle and crack easily
- Not biodegradable
- Pollution from manufacture
- Some are easily scratched
Name 6 types of thermoplastics
Acrylic,
High impact polystyrene,
Polypropylene,
Polythene:
low density (LDPE)
Polythene:
- high density (HDPE)
PVC
What are the properties of acrylic
Stiff, hard but scratches easily, durable, brittle in small sections, good electrical insulator, machines and polishes well.
what are the properties of high impact polystyrene
Light but strong plastic. Widely available in sheet softens at about 95 degrees.
What are the properties of Polypropylene
Light, hard but can scratch easily, tough, good resistance to chemicals, resists work fatigue.
What are the properties of Low density polythene
Tough, good resistance to chemicals, flexible, fairly soft, good electrical insulator.
What are the properties of high density polythene
Hard, stiff, able to be sterilised.
What are the properties of PVC
Stiff hard wearing. Plasticiser can be added to create a softer more rubbery material.
What are some common uses of acrylic
Used for signs, covers of storage boxes, aircraft canopies and windows, covers for car lights, wash basins and baths.
What are some common uses of High impact polystyrene
Used for vacuum forming. Common for school projects which include products outer casings or packaging.
What are some common uses of polypropylene
Used for medical equipment, laboratory equipment, containers - especially with built-in hinges, ‘plastic’ seats, string, rope, kitchen equipment.
What are some common uses of low density Polythene
Used for packaging, especially bottles, toys, packaging film and bags.
What are some common uses of high density polythene
Used for ‘plastic’ bottles, tubing, household equipment and milk crates.
What are some common uses of PVC
Used for air and water pipies, shoe soles, blister packaging.
Name 5 types of thermosetting plastics
Epoxy resin
Melamine formaldehyde
Polyester resin
Urea formaldehyde
Phenol formaldehyde
What are the properties of epoxy resin
Good electrical insulator, hard, brittle unless reinforced, resists chemicals well.
What are the properties of melamine formaldehyde
Stiff, hard, strong, resists some chemicals and stains.
What are the properties of Polyester resin
Stiff, hard, brittle unless laminated, good electrical insulator, resists chemicals well.
What are the properties of Urea formaldehyde
Stiff, hard, strong, brittle, good electrical insulator.
What are the properties of Phenol formaldehyde
A colourless polymer - coloured with artificial pigments to produce a wide range of different colours.
What are some common uses of epoxy resin?
Used for casting and encapsulation, adhesives, bonding of other materials. Used for printed circuit boards (PCB’s) and surface coatings.
What are some common uses of Melamine formaldehyde
Used for Laminating work surfaces, electrical insulation, tableware.
What are some common uses of Polyester resin
Used for casting and encapsulation, bonding of other materials, car bodies, boats.
What are some common uses of Urea formaldehyde
Used for electrical fittings, handles and control knobs, adhesives.
What are some common uses of Phenol formaldehyde
Used for dark coloured electrical fittings and parts for domestic appliances, bottle tops, kettle handles, saucepan handles.
