How do memory substances work?

Have you ever been introduced to memory substances? I am sure you would like to have one after reading my article. Being born with a good memory is a boon that only some people are gifted with. Most of us struggle to memorise - but not this toy. It makes "memorising" sound so easy. Here is how it works. 

Memory Wire

(Video by brussub from youtube.com)

The memory wire or Nitinol wire is an alloy of nickel and titanium and has a unique property of going back to its programmed shape. This was developed in The United States Naval Ordnance Lab, (that is where the name Nitinol comes from). Thinking of it, the memory wire is like a rubber band. Another unique example is our human skin.When we get a cut, our skin tries to recover to its original shape.

Nitinol (also called nickel-titanium) is perhaps the best-known shape-memory alloy. However, there are many more. These include alloys made from copper, zinc, and aluminium; copper, aluminium, and nickel; iron, manganese, and silicon; and quite a few others. You'll also find shape-memory alloys referred under brand names FLEXINOL® and Muscle Wires®. These are proprietary nickel-titanium alloys made by Dynalloy.

As you bend the metal the internal crystalline structure gets disfigured. On exposure to heat, the structure repairs itself by going back to its original form.  Nitinol is ten times more elastic than any other substance. About one foot of nitinol is able to pick up more than one kilogram of weight. It is currently used in bone bonding. 

Do you know why don't we use it in our daily lives? We don't use it because it is rather expensive. 

Memory Foam

Does this photo ring a bell? No? Look at these photos:

Did you get an idea- now here are the few most common uses for memory foam:

1. Bed pillows
2. Travel pillows
3. Mattresses
4. Earplugs
5. Earphone tips
6. Car seats
7. Couches
8. Theatre/auditorium seats
9. Motorcycle saddles
10. Horse saddles

All of these use memory foam. You can squish it into any shape you like and after a few seconds- Bam! It returns into its original shape as if nothing had ever disturbed it. This is handy in earplugs as it becomes easier to put a smaller piece of foam in your ear canal rather than to cram a huge piece into your ear canal and risk getting hurt. 

Memory foam is also known as viscoelastic foam and was developed by NASA as a way to keep test pilots cushioned during the initial take off stage. We all know that after a while the foam returns to its original shape. However, if you keep it compressed for a very long time, the foam becomes deformed. Memory foam also has the property of becoming more softer when it is heated. 

Hope you enjoyed reading this blog. Thank you.