Bimetallic Thermometer

Bimetallic thermometers are made up of bimetallic strips formed by joining two different
metals having different thermal expansion coefficients.
The bimetal sensing element consists of a metal element shaped like a flat spring.  This element is two different metallic materials sandwiched together
On heating of a strip the material,strip bends towards which having less thermal expansion coefficient.pointet is set at the end of the strip and which is moving on the angular or respective scale from which we can directly measure the temperature.
eg.matrial like inver can be used consit of ferus and nikel joined with NI-MO alloy
Advantages:
1)Low cost
2)Low maintaince
Disadvantages:
1)Low responce and opearate at low temp due to creeping

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