GCSE-readySmart and modern materials
Some materials change colour, shape or how they conduct electricity on their own. Others are so strong and light they seem impossible.
Smart materials
| Smart material | Stimulus | What happens | Example use |
|---|---|---|---|
| Thermochromic pigment | Temperature | Changes colour | Mugs that change colour, baby spoons, thermometer strips |
| Photochromic pigment | Ultraviolet (UV) light | Changes colour | Glasses lenses that darken in sunlight |
| Shape memory alloy (such as nitinol) | Heat | Returns to a remembered shape | Medical stents, flexible glasses frames |
| Quantum tunnelling composite (QTC) | Pressure | Insulator becomes a conductor when squeezed | Pressure-sensitive switches |
Modern materials
Graphene: a layer of carbon just one atom thick. Extremely strong and light, and conducts electricity.
Kevlar: a very strong, tough fibre used in body armour and protective gloves.
Carbon fibre: carbon fibres set in resin; very strong and light, used in racing bikes and cars.
Composites
Examples: carbon fibre reinforced polymer, glass reinforced plastic (GRP) and reinforced concrete (concrete with steel bars inside, strong in both compression and tension).
Nitinol is an alloy of nickel and titanium.
A baby's feeding spoon changes colour if the food is too hot. Which smart material is used, and why is it useful?
- The spoon responds to temperature.
- Thermochromic pigments change colour when their temperature changes.
- This warns the parent the food is too hot before the baby eats it.
Answer: A thermochromic pigment: it changes colour with temperature, warning that the food is too hot.
Smart materials respond to a stimulus: thermochromic (heat, colour), photochromic (UV light, colour), shape memory alloy (heat, shape), QTC (pressure, conducts). Modern materials such as graphene and Kevlar have improved properties. Composites combine materials.
- Thermochromic
- Changes colour with temperature.
- Alloy
- A mixture of a metal with one or more other elements, made to improve its properties, such as brass or steel.
- Smart material
- A material that changes a property in response to a change in its surroundings, such as heat or light.
- Modern material
- A material developed through new technology with improved properties, such as graphene or Kevlar.
- Fibre
- Adults should aim for 30 g of fibre a day.
- Composite
- A material made by combining two or more different materials, such as reinforced concrete or carbon fibre.
Try two quick questions
See if it has sunk in. Answers are marked straight away.
2 more questions
Try each one, then tap to check.
Which is an example of a smart material?
- A plain wooden spoon
- A steel nail
- A cotton T-shirt
- A mug that changes colour when hot drinks are poured in
Show the answer
Answer: A mug that changes colour when hot drinks are poured in
Thermochromic pigment reacts to heat.
A baby spoon changes colour if food is too hot. Which material does it use?
- Photochromic pigment
- Shape memory alloy
- Thermochromic pigment
- QTC
Show the answer
Answer: Thermochromic pigment
Thermochromic reacts to heat.
Check you have got it
Answer 7 quick questions with instant marking. If you get one wrong, GCSE-ready shows you why and gives you another go. It is free, and you do not need an account.
Last updated 2 October 2026. Spotted a mistake? Tell us and we will fix it.