Materials and Their Properties

material categories

traditional materials
modern materials
smart materials

material classifications

metals
woods/timbers
polymers
paper and boards
composites
smart and modern materials

wood/timber structure

fibrous materials made up of plant cells (cellulose fibres) and natural resins

metal structure

made up of crystals containing atoms and molecules

papers and boards structure

derived from wood, sharing the same molecular structure

fibrous materials made up of plant cells (cellulose fibres) and natural resins

polymer structure

long chain molecules containing carbon, hydrogen and oxygen atoms, along with other chemicals like chlorine and fluorine

physical properties

refer to the actual makeup or structure of the material

fusibility

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

density

defined as mass per unit volume

electrical conductivity

a measure of how well a material accommodates the movement of an electrical charge

electrical insulation

high resistance to the flow of electricity

semi-conductors

range between conductors and insulators, allowing current flow under certain conditions

thermal properties

how a material reacts to heat (expansion, conductivity, and insulation)

opacity

how much light is allowed to pass through. opaque materials do not allow light to pass through, while semi-opaque materials allow some light through (translucency)

transparency

ability for light to fully pass through, allowing visibility through the material (e.g., glass)

translucency

ability to transmit light even if you cannot clearly see through the material (e.g., thin paper)

colour

perceived by light reflecting off the surface, considered an optical property

surface

how light bounces off indicates smoothness or roughness

mechanical/working properties

refers to how a material reacts or behaves when exposed to a stimulus/external force

plasticity

ability to be permanently changed in shape by an external force without damage.

malleability

ability to withstand deformation by compression.

ductility

ability to be drawn out (stretched).

elasticity

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

toughness

ability to withstand a sudden impact; can also refer to bending resistance.

hardness

ability to withstand abrasive wear (indentation or scratching).

durability

ability to withstand wear and tear, weathering, and corrosion.

stability

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

strength

ability to withstand forces without breaking or being permanently deformed.

tensile strength

ability to withstand stretching or pulling forces.

compressive strength

ability to withstand pushing or crushing forces.

bending strength

ability to withstand forces that attempt to bend a material.

shear strength

ability to withstand sliding forces acting against each other.

torsional strength

ability to withstand twisting forces.