The Properties and Uses of Smart Materials

Smart materials are those that can change their physical properties in response to changes in their environment.
Two common types of smart materials are shape memory alloys and piezoelectric crystals.
Shape memory alloys: These materials can recover their original shape after deformation when heated. This property is due to the way their particles are bonded and structured, enabling them to ‘remember’ their original shape.
One use of shape memory alloys is in dental braces. When the alloy wire is cooled, it becomes flexible, making it easy to fit into the mouth. Once in position, the warmth of the mouth causes the wire to stiffen and revert back to its original shape, applying a gentle, constant force that guides teeth into their new positions.
Piezoelectric crystals: These can generate an electric current when compressed. This is a consequence of the shifting alignment of the positive and negative charges within the material when deformed.
One application of piezoelectric crystals is in the creation of smoke alarms. When particles of smoke enter the alarm, they interrupt a small electrical current created by piezoelectric crystals. This interruption triggers the alarm to sound.
Another example of a smart material is polymorph, which softens and can be moulded at relatively low temperatures, but is hard and firm at room temperature.
Polymorph can be used to create bespoke moulds, repair materials or prototype designs. It can be reheated and reshaped multiple times, which makes it an eco-friendly choice as it can be reused.
Understanding the specific properties and uses of smart materials can help in making decisions regarding which material is most suitable for a particular purpose.
The bonding and structure of smart materials directly contribute to their unique properties, making them useful in a wide range of industrial applications.
It’s also important to consider the environmental implications of using smart materials, such as their ability to be recycled or their potential detrimental impact if not disposed of correctly.