How is induction heating used to anneal wire?
Induction heating creates eddy currents in the wire, heating it precisely and quickly.
Induction heating is used annealing wire by passing an alternating current through a coil which creates an electromagnetic field around the wire. This magnetic field induces eddy currents in the wire, causing it to be heated. This precise process heats only the wire and does so very quickly, typically heating the wire to a temperature above its recrystallization temperature, between 500 and 700 degrees Celsius (932 and 1292 degrees Fahrenheit). The induction annealing process helps to relieve the stresses in the wire that were caused during the drawing process, leaving the wire more ductile and less likely to break.