The wonderful thing about a simple clip: crystals at the speed of sound

A clip is one of the seemingly insignificant everyday objects. It is only a very small piece of metal that serves to capture leaves and little else. But nevertheless, a clip is an almost legendary object if we examine it with a little more detail.

Because a clip is actually made of crystals that move from side to side at the speed of sound.

Metal made of crystals

At first glance, a metal does not seem to be made of crystals because the metallic crystals are opaque and, in most cases, microscopic. As he explains Mark Miodownik in his book Material (and) things:

Seen with an electron microscope, they look like a very irregular tiling, and in each one there are undulating lines: they are dislocations or defects of the crystalline structure.

These disturbances in atoms allow metals to change shape. For example, fold a clip. When we fold a clip, we actually bend the crystals that form the metal.

This plasticity is produced by dislocations, which move within each crystal by moving small fragments of material from side to side at the speed of sound. Thus, folding the clip causes one to move approximately 100,000,000,000,000 dislocations at a speed of hundreds of meters per second. If each one displaces only a tiny piece of glass, they are numerous enough to allow the metal to behave like a super-resistant plastic, and not like a stone.

Video: The Coolest Things Sound Waves Do (February 2020).