Technical Principles - Smart Materials

Definitions SMAs Types

Smart Material

A material that changes its physical properties in response to a stimulus.

Shape Memory Alloy (SMA)

A material that when heated or a current is put through it, will return to its original shape. E.g. Braces, glasses frames. Materials include Nitinol.

Name 3 examples of smart materials.

• SMAs like Nitinol

• Thermochromic Pigment

• Phophorescent Pigment

• Photochromic Pigment

• Electroluminescent wire

• Piezoelectric material

Thermochromic Pigment

Changes colour in response to temperature. E.g. Children’s bath toys.

Phophorescent Pigment

Absorbs light during the day and ‘re-emits’ the light energy when it gets dark. E.g. Fire exit signs

Photochromic Pigment

Changes colour depending on light intensity. E.g. Welding Goggles

Electroluminescent Wire

A copper wire that glows when an AC is applied to it. E.g. Glow Bracelets

Piezoelectric Material

Gives off a small electric charge when deformed. E.g. Airbag sensors in cars.