Material Properties

Learning Intention:Understand the terms used to

describe the properties of materials

Material Properties

Different materials have different properties

Designers have to consider these properties when selecting the most suitable material for a specific product

Selecting Appropriate Materials

When mass producing a product you would need a material that can be permanently shaped and easily formed

Selecting Appropriate Materials

If you were building a bridge, you would need a material with the ability to withstand high forces

When describing a material’s properties we can refer to either its Mechanical Properties or its Physical Properties

Mechanical Properties

The Mechanical Properties of materials are linked to how they react to the application of force

Types of Force

Mechanical Properties - Strength

The strength of a material is its ability to withstand an applied force without breaking or bending permanently

Materials can have different types of strength – thinking of the different types of force what do you think they are?Here’s the first one

Tensile Strength

Bending Strength

Compressive Strength

Shear Strength

Torsion Strength

Mechanical Properties - Hardness

The ability of a material to resist abrasive wear or scratching

Mechanical Properties - Density

The mass per unit volume – often has an effect on other properties such as hardness

Mechanical Properties - Durability

The ability to resist wear and tear (over a period of time, materials begin to weather and suffer wear and tear

Mechanical Properties - Toughness

The ability to withstand sudden shocks or blows without breaking

Mechanical Properties - Brittleness

The opposite of toughness – little or no resistance – acrylic is very brittle unless heated

Mechanical Properties - Malleability

The ability of a material to be permanently deformed in all directions – hammering, rolling or pressing

Aluminium Cans

Mechanical Properties - Elasticity

Ability to flex and bend but return to original form when force is removed

Mechanical Properties - Ductility

Ability of a material to be cold-formed by being pulled (drawn) into thinner sections of wire (without breaking)

Physical Properties

The Physical Properties of materials are unaltered by the application of force

Physical Properties - fusibility

Ability of a material to change into a liquid at a certain temperature – important for fabrication and forming processes

Physical Properties – thermal conductivity

Ability to allow heat to pass through a material

Physical Properties – Electrical conductivity

Ability to allow electricity to pass through the material

Physical Properties – Environmentally friendly

Materials that can be reused, recycled or are biodegradable

Examiner’s Tip

•You must be able to describe the properties of

materials

•Be able to describe the terms used in relation to

a variety of materials using notes and sketches

Examiner’s Tip

•You must be able to describe the properties of

materials

•Be able to describe the terms used in relation to

a variety of materials using notes and sketches

Homework Task

• Design some simple tests you could carry out in the school workshop to find out the relative properties of a range of materials

Check your understanding

the ability of a material to conduct heat or electrical energy

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Check your understanding

Give an example of a material with good thermal conductivity

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Check your understanding

Give an example of a material that is a good thermal insulator

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Check your understanding

Give an example of a material that is a good electrical insulator

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Check your understanding

the ability of a material to withstand a force without breaking or bending

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Check your understanding

Why would this I beam be used?

Check your understanding

the ability of a material to bend and then to return to its original shape and size

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Check your understanding

Many wooden tool handles and sports equipment are made from Ash. Why?

Check your understanding

the ability of a material to permanently deform in all directions without cracking

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Check your understanding

Give an example of a malleable metal

Check your understanding

the ability of a material to deform, usually by stretching along its length

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Check your understanding

Name a metal that is ductile – what is it used to make?

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Check your understanding

the ability of a material to resist wear, scratching and indentation

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Check your understanding

the ability of a material to withstand blows or sudden shocks without breaking

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Check your understanding

What’s the opposite of tough? Give some examples

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Check your understanding

is the ability of a material to withstand wear, especially as a result of weathering

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Check your understanding

the ability of a material to change into a liquid or molten state when heated to its melting point

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