Curie Point Of Iron

Purpose

To show the Curie point of iron.◙
 

Equipment

Pre-assembled Curie point of iron demonstrator.◙

 

Images

j7-12

Description

An iron wire is normally ferromagnetic, and therefore strongly attracted to the magnet as shown in the photograph. When heated so that it glows red hot by passing an electric current through it, the iron rises above its Curie point and loses its ferromagnetism, so springs at either end of the wire pull it away from the magnet.◙
 

References

G. J. Van der Maas and W. J. Purvis, "Curie point" Motor, AJP 24, 177-178 (1956). ◙R. Stuart Mackay, On Curie Point Motors and Oscillators, AJP 27, 185-186 (1959). ◙Harald C. Jensen, New Demonstration of the Hysteresis Loop in Iron, AJP 25, 384-385 (1957). ◙P. G. Mattocks, A 0.7-mW magnetic heat engine, AJP 58, 545-548 (1990). ◙David G. Fisher and William T. Franz, Undergraduate laboratory demonstration of aspects of phase transitions using Curie◙temperature determination in amorphous ferromagnetic materials, AJP 63, 248-251 (1995). ◙Handbook of Tables for Applied Engineering Science, Table 2-