IntermediateTopic 57 of 100Materials & Chemical
Smart materials
Piezoelectric, shape-memory and magnetostrictive materials respond to stimuli.
In depth
Smart materials respond to stimuli: piezoelectrics (strain↔voltage), shape-memory alloys (NiTi: thermal recovery), magnetostrictive and electrostrictive materials, electro/magnetorheological fluids, thermochromics and self-healing polymers. Used in sensors, actuators and adaptive structures.
Key points
- Martensite-austenite transformation
- Superelasticity
- Energy harvesting
ExampleNiTi stents expand to shape at body temperature.
Smart materials respond to stimuli such as electric fields or temperature, which allows sensors, actuators and self-adjusting structures.
What is Smart materials?
Piezoelectric, shape-memory and magnetostrictive materials respond to stimuli.
Why is it important to understand smart materials?
Smart materials respond to stimuli such as electric fields or temperature, which allows sensors, actuators and self-adjusting structures.
What is a piezoelectric material?
A material that generates charge when stressed and changes shape when a voltage is applied, which makes it useful as a sensor and actuator.
What is shape memory?
Some alloys return to a set shape after deformation when heated, which is due to a reversible phase transformation.
How is Smart materials used in practice?
Typical applications include using a piezoelectric crystal as a sensor in a pressure transducer, designing a shape-memory alloy actuator for a valve and building a magnetostrictive sensor to measure force on a rod.
What should I learn before Smart materials?
Study "Nanomaterials" first (topic 56 of 100 in Materials & Chemical). It covers the groundwork this topic builds on.
What are the key points of Smart materials?
Martensite-austenite transformation. Superelasticity. Energy harvesting.
Can you give an example of Smart materials?
NiTi stents expand to shape at body temperature.
What comes after Smart materials?
The next topic is "Materials selection", which builds directly on this one.
How difficult is Smart materials?
It is classed as Intermediate in Materials & Chemical (topic 57 of 100). It is an intermediate topic. Work through the beginner topics in Materials & Chemical first.