Thermal Expansion - Bimetal Strip

Purpose

To demonstrate differential thermal expansion.
 

Equipment

Bimetal strip with burner.

 

Images

i1-13

Description

Strips of invar steel and brass are welded together to form a bimetal strip. Because their coefficients of thermal expansion are different, heating the bimetal strip over a burner results in bending, as illustrated. This type of material is used in some types of thermostatic controllers.