Material properties Flashcards
(72 cards)
Material working properties (7)
-Hardness
-Ductility
-Elasticity
-Density
-Toughness
-Malleability
-Strength
Hardness
The ability to withstand scratching, denting and abrasion
e.g. oak: flooring, furniture
tools that cut: files, drills
Ductility
Materials that can be stretched into a wire
e.g. copper: copper wires
Elasticity
The ability to be stretched and return to the original shape
e.g. elastane: lycra sportswear
Density
A material’s mass per unit volume
e.g. lead: shield for x-rays
Toughness
Materials that are hard to break or snap
e.g. kevlar: bullet proof vests
Malleability
Being able to bend or shape easily
e.g. sheet metal (steel/silver): car body panels
Strength
A material’s ability to withstand a constant force without breaking
e.g. woven wool: clothing
Forces used to test strength (5)
-Compression (push into a material)
-Shear (compress the material from different places)
-Tension (pull the material apart)
-Bending (tension on one side, compression on the other)
-Torsion (twisting the material in opposite directions)
Material physical properties (5)
-Absorbency
-Resistance to moisture
-Thermal conductivity
-Electrical conductivity
-Fusibility
Absorbency
The material’s ability to soak up or retain liquid
e.g. paper: paper towels, tissues
Resistance to moisture
The material’s ability to prevent liquid and moisture permeating its surface
e.g. PVC (a polymer): waterproof coats
Thermal conductivity
How easily heat energy can pass through a material
e.g. aluminium: foil, pots and pans
Electrical conductivity
How easily electrical energy can pass through a material
e.g. copper: electrical wires, circuits
Fusibility
How easily a material’s state can be altered to become a liquid
e.g. silver: jewellery, solder
Metal properties
-Strong
-Malleable
-Good electrical and thermal conductors
-Not very fusible (high melting point)
Non-metal properties
-Brittle
-Not always solid at room temp
-Poor electrical conductors
-Dull looking
-Less dense
Alloys
A mixture of two or more metals
-Developed to have a specific set of properties
Types of paper (5)
-Cartridge paper: high quality, textured suface
-Layout paper: thin, translucent
-Tracing paper: semi-transparent
-Grid paper: square or isometric pattern
-Bleed-proof paper: ink doesn’t spread
Types of boards (6)
-Solid white board: high quality, bleached surface for printing, used for primary packaging
-Ink jet card: ink doesn’t bleed
-Corrugated card: layer of triangles (fluted inner core) between two layers of card, strong and rigid
-Duplex board: different colour and texture on each side, used for food packaging
-Foam core board: polystyrene foam sandwiched between 2 thin layers of card, lightweight, used to make models
-Foil lined card: lined with aluminium foil, used to package food, keeps food warm
Softwood definition and examples
Usually evergreen trees grown in cooler climates. Grow fast so readily accessible and cheap.
-Pine
-Larch
-Spruce
Hardwood definition and examples
Grown in warm climates and are slow growing making them expensive. Deciduous (lose leaves) with a tighter grain which is appealing.
-Oak
-Mahogany
-Beech
-Balsa
-Ash
Pine
SOFTWOOD
Yellow with brown streaks
Properties: strong, cheap, knotty so hard to work with
Uses: telegraph poles, fences, cheap furniture
Larch
SOFTWOOD
Attractive yellow/reddish-brown
Properties: hard, tough, durable, resistant to rotting
Uses: cladding for buildings, fence posts