Materials and their working properties Flashcards
What is absorbency?
The ability of a material to take in or soak up something usually a liquid, but sometimes heat and light
Examples of materials that are generally good absorbers of liquid
Papers, boards and natural fibres
What is a physical property?
They relate to the actual material
List the five physical properties
Absorbency density, fusability, electrical conductivity, thermal conductivity
What is. Density
Materials mass per unit volume (how compact it is!)
How is density commonly measured
In g/cm cubed or KG/centimetre cubed
Give an example of a dense material
Metals are usually dense
What is fusibility
The ability of a material to be converted into molten or liquid state through heating
Describe the properties of a material that has been converted into the molten state
They have a low, melting point and have a high fusibility
Give an example of material with high fusibility
Solder. It is used to fuse together materials because it’s melts before the metal been joined melts
What is electrical conductivity?
The ability of a material to conduct electricity
Give an example of a good electrical conductor and a poor electrical conductor
Metals are generally good electrical conductors.
Plastics tend to be poor conductors, so they are called insulators
What happens as a result of a poor conductor being paired with a good conductor of Electrical energy
Electrical wiring is often made from copper that is in case I a flexible plastic
What is thermoconductivity?
We ability of a material to conduct heat
Give an example of a good thermal conductor and a poor thermal conductor
Metals are good, thermal conductors and plastic up for thermal conductors
What is the result of adding a poor thermal conductor and a good thermal conductor together
Example a frying pan as they’re often made from aluminium with plastic handles
What are working properties?
They relate to how much a material responds to external forces and/or conditions
List the six working properties
Strength, hardness, toughness, malleability, ductility, and elasticity
What is elasticity?
The ability of a material to return to its original shape after being stretched, bent or compressed
What is ductility?
The ability of a material to be stretched or pulled into a strand without breaking
What is malleability?
The ability of a material to be bent and shaped without breaking
What is toughness?
The ability of a material to absorb energy without fracturing
What is hardness?
The ability of a material to resist wear, abrasion, scratching or denting
What is strength?
The ability of a material to withstand force without breaking
Give five examples of forces (strength)
Pressure tension compression sheer or torsion
What might materials be in terms of strength? And eg
Strong and one force but weak in another
Eg: Concrete is strong in compression, but weak in tension
How are papers and board classified?
Classified based on their weight in grams per square metre (gsm)
Anything under what weight is generally considered a paper
Under 200 GSM
Anything over the weight of 200 GSM is considered what
To be aboard
What are papers and boards made from?
Natural fibres (cellulose) from wood and recycled waste paper
What are the five types of paper?
Bleed proof paper
cartridge paper
grid paper
layout paper
tracing paper
What are the physical properties of bleed proof paper?
A smooth, thick paper that prevents ink from seeping and bleeding
What are the uses of bleed proof paper?
Quality, presentational drawings
What are the physical properties of cartridge paper?
creamy white paper, usually with a lightly textured surface
What are the uses of cartridge paper?
Drawings in pencil, charcoal, or pastel as well as paintings
What are the physical properties of grid paper?
White paper with a printed grid of isometric lines or squares
What are the uses of grid paper?
Scale, drawings, quick sketches and modelmaking
Physical properties of layout paper
Thin , relatively transparent paper with a smooth surface
What are the uses of layout paper?
General design, work, and sometimes Tracing
What are the physical properties of tracing paper?
Thin, transparent paper with a smooth surface
What are the uses of tracing paper?
Copying and tracing designs
What are the uses of tracing paper?
Copying and tracing designs
Name the six types of board
Corrugated card, duplex board, foil lined board, foam core board, inkjet, card and solid white board
What are the properties of corrugated card?
Two or more layers of card with a fluted layer in between to add strength
Uses of corrugated card
Packaging and boxes to protect items from damage
Physical properties of duplex board
Cheaper than white card, usually has one smooth white side (often printed )
Uses of duplex board
Food packaging that requires printing on one side
Physical properties of foil lined board
Cord lined with aluminium foil on one side to provide insulation
Uses of foil lined board
Takeaway food packaging
Physical properties of foam core board
Two thin layers of card with a foam inner core in between
Uses of foam core board
Model making and mounting pictures
Physical properties of inkjet card
Smooth, treated card for a high quality, bleed proof finish
Uses of inkjet card
High quality photographs
Physical properties of solid whiteboard
Strong, high quality bleach card that is perfect for printing
Uses of solid white board
High quality packaging, printing, and book covers
Where do most hardwoods come from?
Broadleaved deciduous trees, they are generally slow growing, and therefore usually more scarce and expensive than softwoods
Name the four main types of hardwood
Beach, oak mahogany, and Balsa
Properties of beech
Hard tough,strong and finish as well.
Warps easily.
Close straight grain.
Expensive?
Pinkish, brown
Uses of beech
Flooring, furniture tool handles
Properties of oak
Very strong, heavy durable and hard
Grain varies, but is generally open
Over 400 species.
Light brown
Uses of oak
Flooring
Furniture
Barrels
Properties of mahogany
Hard,strong, easy river work, rot resistant
Fine, straight grain
Some species are protected
Reddish brown
Uses of mahogany
Flooring
Fine furniture
Instruments
Properties of balsa
Very light and soft
has great strength-to-weight ratio
Straight grain with distinct velvety feel
Pale cream to white
Uses of balsa
Surfboards
Construction
Air craft models
What are soft woods?
Come from coniferous trees that have long needle like leaves
Generally found in cold climates.
Quick growing so can be replaced quicker than hardwoods
4 main types of soft Wood
Cedar
Scots pine
Larch
Spruce
Properties of cedar
Contains a chemical that makes it durable and weather resistant
Short, notable grain
Light cream to reddish brown
Uses of cedar
Outdoor furniture
Cupboards
Fencing
Properties of Scots pine
Easy to work with
Reasonably strong and lightweight
Straight grain with lots of knots
Pale and reddish brown
Uses of Scots pine
Furniture
Construction
Door frames
Properties of larch
Tough and strong but easy to work
Resistant to rot but prone to splitting
Yellow to reddish brown
Uses of larch
Decking
Cladding
Fencing
Properties of spruce
Good strength-to-weight ratio
Can contain small knots
Creamy white to pinkish brown
Uses of spruce
Construction
Stringed musical instruments
Name 4 other hard woods
Ash
Birch
Maple
Willow
Name 3 more soft woods
Douglas fir
Yew
Western hemlock
What does MDF stand for?
Medium- density fibreboard
How is MDF made?
Wood chips are broken down into pulp and then mixed with glue and then compressed
Properties of MDF…..
smooth surface- easy to paint and finish (often with high quality veneer)
Denser than other manufactured board
Produces hazardous dust- mask should be worn when using
Uses of MDF…
Flat pack furniture
Kitchen units
Interior panelling
Comes in moisture and fire resistant varieties
