Smart Materials

Smart materials are those materials which have properties which react to the environmental changes. In other words, smart materials are those materials which their properties change with the change of the external conditions like electricity, light, magnetic field, temperature, pressure and moisture. However, these changes are reversible and can be recurred several times. There are a broad range of various smart materials which each offers various properties that are reversible. Most of these materials are reactive. Smart materials includes, smart colours, polymorph, smart grease, conductive polymers and nanomaterials among others.

Smart Colours and Applications

Smart colours are pigments that can be involved into dyes, plastics, inks and paints such as thermo chromic pigments. These pigments act in response to changes in temperature through colour changes. Thermo chromic pigments are commonly used in contact thermometer particularly those made from test strips and plastic strips on both ends of batteries. Thermo chromic pigments are as well applied in food packaging material which indicates when the product packed in is cooked to the right temperature.

Photo chromic pigments are other forms of smart colours. However, these are reactive to changes in levels of light. When the level of light levels goes high, the colour of these pigments darkens while when the level of light goes down, the colour brightens. This property of these pigments makes them very useful in making sunglasses to protect the eyes from excessive light.

Examples Of Smart Materials And Their Applications

Most materials when are bent out to form a new shape, they remain in that shape. Nevertheless, when a piece of shape-memory alloys is bent into a certain shape, and heat applied on it, at particular temperature, the shape returns to its original shape before it was force to bend. However, on cooling the shape-memory alloy goes back to it bending shape. This property makes shape-memory alloys to be very useful in development of spectacle frames since they gain their original shape when inserted in hot water after they are bent. This property makes shape-memory alloys to be used as controller for valves in hot water showers, sprinklers in fire alarms system and in spectacle frames.

Piezoelectric materials are another form of special material that reacts to external conditions through emission of small electrical current which last for a short while. When rapidly squeezed, piezoelectric materials generate minute electrical voltage which leads to slight change in its shape. This property makes piezoelectric material to be used as contact sensors in alarm systems, headphones and microphones.