This exciting demonstration allows students to see the effects cold working (bending or flattening) has on the ductility of copper wire, and the effects of annealing (heating) on the ductility. -- Cold working the wires introduces defects known as dislocations into the crystal structure of the metal. The more defects that are introduced, the harder and stronger the copper becomes, making further cold working increasingly difficult. -- Annealing the cold worked copper eliminates the dislocations, resulting in increased ductility. -- Includes: 10 copper wires, frame and handle, instructions with diagrams. Required but not included: bunsen burner and gas source, pliers, large beaker of water, permanent magic marker, phillip’s screw driver (for assembly of frame). |
