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Why the Towers Fell
The Structure of Metal
Move

Diagram of metal crystals when metal atoms move

The atoms that comprise a metal are tightly bound to one another by the metallic bond, as explained in Metal Basics. But if enough force is applied, these atoms are able to slip into a new position.

This section shows how the atoms move. The points in the above illustration represent atoms. The lines between the points are the bonds that hold the atoms together.

When a force is applied, the top two rows of atoms shifted to the right, but not all at once. Instead, they moved two at a time, bumping and displacing the next two atoms. This movement required only one bond to break at a time (in this two-dimensional structure). To move all the atoms in the top two rows at once would have required many bonds to break at once and thus a great deal more force. The rearranged atoms are as tightly bound to one another as they were before the shift.

Although this bumping and then displacing action is not shown in the Slip and Bend sections of this feature, the atoms in these sections move similarly when displaced.

To continue to the next section, select Slip.

Metal Basics | Move | Slip | Bend | Heat


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