Curvature of a Bimetallic Beam


A bimetallic strip is used to convert a temperature change into mechanical displacement. The strip consists of two strips of different metals which expand at different rates as they are heated. The different expansions force the flat strip to bend one way if heated, and in the opposite direction if cooled below its initial temperature. The metal with the higher coefficient of thermal expansion is on the outer side of the curve when the strip is heated and on the inner side when cooled. The curvature of a Bimetallic Beam is related to Young’s Modulus and the height of Materials and the misfit strain.

Related formulas


kCurvature of a Bimetallic Beam (dimensionless)
E1Young's Modulus of material one (dimensionless)
E2Young's Modulus of material two (dimensionless)
h1Height of material one (dimensionless)
h2Height of material two (dimensionless)
ϵThe misfit strain (dimensionless)