Bimetallic strip introduction
A bimetal is a composite of two or more metals or other materials having suitable properties. Bimetals are also called hot bimetals. Because of the different thermal expansion coefficients of each component layer, when the temperature changes, the deformation of the active layer is greater than the deformation of the passive layer, so that the whole bimetal is bent toward the side of the passive layer. Then, the curvature of the composite material changes to cause deformation.