To measure the Curie temperature of a body where the body losses its ferromagnetic property and changes to a paramagnetic state if it is further heated.
An inductor with Ferrite core [ sample] connected to an ac source along eith a resistor . The sample keep on the temperature bath . Increase the temperature and measure the potential drop across resistor .
We know that the current across the resistance and the inductance is:
And L = X X constant
This constant depends on several geometrical factors.
X = magnetic susceptibility
When the sample is in Ferro state X is large and hence L is large which implies I is small.
After the transition takes place to the Para state with gradual increase in temperature, magnetic susceptibility decreases thereby decreasing L and I increases.
The setup consists of :
- Ferrite core inductor (sample).
- Sinewave generator 50 KHz [ Max.].
- Digital frequency counter.
- AC voltmeter 3 ½ digit.
- Heater with sand bath.
- Temperature sensor with Microcontroller based Temperature indicator.
