Nitinol Teaspoon

Offer someone this teaspoon to stir their tea or coffee. As soon as they dip it into the hot liquid, the spoon bends through 90 degrees! It does this very quickly and will cause the person holding the spoon quite a surprise! Alternatively, you can stir your coffee or tea in a café or office canteen and then point out how strong the tea or coffee must be, given it has caused the spoon to bend! Finally, there is a perfect depth of tea or coffee, where you can drop the spoon in and it will vanish below the surface, due to it bending the minute it enters the hot liquid. The liquid needs to be deep enough to cover the spoon in the bent position, but not so deep that people will think it is deep enough simply to cover the spoon without it bending. If you use a cup and saucer (the saucer covering more than a mug would) you can then lift the cup and saucer off your hand and reveal the teaspoon underneath – it appears the spoon has passed through the cup and ended up in your hand! Of course, you need two spoons to perform this particular trick.

The liquid does not need to be boiling - the spoon will sometimes bend if placed under water from the hot tap, if it is hot enough. Part of the handle is made of Nitinol or Shape Memory Metal, which 'remembers' a shape that has been previously set into it. To reset the spoon, first cool it under the cold tap, and then straighten it again. The spoon can be used many times, as Nitinol is a very flexible metal.

Nitinol is a metal alloy, sometimes also called 'memory metal' or more properly Shape Memory Alloy (SMA). This memory effect was originally discovered in the 1930s, but Nitinol itself was only discovered in 1962. Made from Nickel and Titanium, it was discovered at the Naval Ordnance Laboratory in White Oak, Maryland.

Shape Memory Alloys have two distinct types of crystal structure, depending on whether they are above or below a certain critical transformation temperature. Below the critical temperature, the alloy is flexible and can be bent easily into any shape. This is known as the martensitic state, where the atoms are in flexible lattices, which allow the metal to be bent easily. But once heated to the critical temperature, Nitinol shows its 'heat memory' as it transforms into the austenitic state, where the atoms become locked into their previous rigid arrangement. When the metal springs into its remembered shape, it does so with so much force that it can be used to do actual work. Small motors have been built using Nitinol wire that passes through different temperatures. Solar panels on some satellites are raised into position by Shape Memory Alloys, activated by the heat of the sun.

A shape is programmed into a piece of Nitinol by annealing it. The metal is held in the desired shape and heated to a very high temperature. After it cools, you can bend it into any shape you want but heat it above the critical temperature (which is much lower than the annealing temperature) and it will instantly return to the high temperature shape that you programmed into it.

Made in EU

SUITABLE FOR AGES 14+