Credit: Jason Regan
License: CC BY-NC 3.0
Got braces? If so, you may have a cool type of alloy in your mouth!
Amazing but True!
- Alloys are mixtures of metals that have properties that the individual metals don’t have. One property of some alloys is the amazing ability to change shape.
- These alloys are called shape-memory alloys. The alloy named nitinol is an example. It’s a mixture of the transition metals nickel and titanium. Nitinol is used in braces to apply pressure to teeth and gently move them into new positions.
- Watch this video to learn the science behind nitinol and other shape-memory alloys: http://ed.ted.com/lessons/ainissa-ramirez-magical-metals-how-shape-memory-alloys-work
What Do You Think?
At the links below, learn more about shape-memory alloys and their uses. Then answer the following questions.
- The science behind shape-memory alloys starts with atoms. How do atoms naturally arrange themselves?
- How do atoms of shape-memory alloys change when heated?
- What are some practical applications of shape-memory alloys?
- If you bend or twist a nitinol wire, how can you get it to return to its original shape?
- What are two limitations on shape-memory alloys?