Cambridge Design & Technology students have to be familiar with smart materials and their common applications and uses. This article includes illustrated examples of smart materials and provides sample examination questions to help you revise this topic.

What are smart materials? (A definition)
Smart materials are those that respond to a change in the environment or to a new input – for example, materials that change in response to electricity, temperature, pressure, or light. Smart materials change in a reversible way, so when the external stimuli is removed, they return to their original form.
Note: Some students get confused and think this topic might be related to ‘smart’ phones or advancements in technology. However, ‘smart’ in this context relates to the material’s ability to change its form in response to an external stimuli.
Examples of smart materials
SMART PIGMENTS (coloured powders in paint etc)
Phosphorescent pigments
Properties
Uses
Photochromic pigments
Properties
Uses
Thermochromic pigments
Properties
Uses
SHAPE MEMORY ALLOYS (SMA)
Nickel-titanium
Properties
Uses
Copper-aluminium-nickel
Properties
Uses
Shape memory means it ‘remembers’ its prior shape and returns to that shape when heated to a specific temperature.
OTHER SMART MATERIALS
Hydrogels
Properties
Uses
Shape memory polymers
Properties
Uses
Modern and smart materials are constantly being engineered, so it’s good to try to keep up to date with the latest developments. They can often be incorporated into new consumer products without people noticing.
Smart materials are a type of modern materials (although not all modern materials are smart).