1.1 Material Properties

What are the three categories of materials?

Modern, Traditional, and Smart materials.

What are traditional materials and give examples

Materials that have been used for many centuries

Ancient Materials: Stone, wood, textiles, iron, and bronze.

What are modern materials and give examples

Materials developed in the last century

Titanium, polymers, concrete, composites and even materials which were once considered as smart materials but as time went on were no longer smart materials

What are smart materials and give examples?

Materials that change their physical properties in response to external stimuli, such as thermochromic pigments and shape memory alloys, ferrofluid

What are the main classifications of materials for product design?

Metals, Timber/Woods, Polymers, Paper and board, Composites, Smart and modern materials.

What determines the properties of a material and give examples

The properties of a material are determined largely by its structure

Metals are made up of crystals that contain atoms and molecules

Woods are fibrous materials made up of an arrangment of plant cells and resins.

Paper and card are derived from wood and therefore share the same molecular structure

Polymers are made up of long chain molecules containing carbon, hydrogen and oxygen atoms, along other chemicals such as chlorine and flourine

What are physical properties of materials?

Characteristics that refer to the actual makeup or structure of the material.

Name All Physical Properties

fusibility

density

electrical conductivity

electrical insulation

semi-conductors

thermal properties

opacity

transparency

translucency

colour

surface

Chemical resistance

Corrosion resistance

What is fusibility?

The ability to change into a molten or liquid state when heated to a certain temperature.

Define density

Mass per unit volume; relative density is the ratio of the substance's density to that of pure water at 4 degrees Celsius.

What is electrical conductivity?

The ability of a material to allow the flow of electricity, with conductors offering low resistance.

What is electrical insulation

these offer a high resistance to the flow of electricity.

What are semi-conductors?

range between electrical conductivity and electrical insulation and allow electric current to flow under certain conditions.

Define thermal properties

how a material reacts to heat such as expansion, conductivity and insulation.

Define opacity

How much light is allowed to pass through. A fully opaque material will not allow light to pass through, while a semi opaque material will allow some light through

What is the difference between transparency and translucency?

Transparency allows light to fully pass through, while translucency allows some light through without clear visibility.

Define colour

the percieved colour we see when light bounces off the surface of a material therefore this could be classed as an optical property.

Define surface

How light bounces off a material gives an indication of how smooth or rough the surface of the material is.

Define corrosion resistance

will not rust or degrade from contact with water

Define chemical resistance

will not degrade with detergents

What are mechanical properties of materials?

Characteristics that refer to how a material reacts to external forces.

Name all the Mechanical Properties

plasticity, malleability, ductility, elasticity, toughness, hardness, durability, stability, strength

What is plasticity in material properties?

The ability of a material to be permanently changed in shaped by an external force without damage.

Define malleability.

The ability to withstand deformation by compression, without breaking

What is ductility?

The ability of a material to be drawn out or stretched.

What does elasticity refer to in materials?

The ability to flex and return to its normal shape when the force is removed.

What is toughness in material properties?

The ability to withstand sudden impact and bending.

What is hardness

The ability to withstand abrasive wear (indentation or scratching)

Define durability

The ability of a material to withstand wear and tear as well as weathering and corrosion.

Define stability

The ability to resist changes in shape and size due to its environment.

Define strength

The ability to withstand forces without breaking or being permanently deformed.

What is tensile strength?

The ability to withstand stretching or pulling forces.

What is compressive strength?

The ability to withstand pushing or crushing forces.

What is bending strength?

The ability to withstand forces that attempt to bend a material.

What is shear strength?

The ability to withstand sliding forces acting against each other.

What is torsional strength?

The ability to withstand twisting forces.