A composite consisting of two distinct metal layers permanently bonded together, usually by cladding, welding or rolling. The metals are chosen for their contrasting properties, most commonly their differing coefficients of thermal expansion. This causes the combined piece to bend predictably when heated or cooled, making it useful for temperature switches, thermostats and circuit breakers.
Check the bimetal in that breaker, it might be fatigued from tripping too many times.
The bond between the layers must be metallurgical rather than mechanical, otherwise repeated thermal cycling will cause the metals to slip or separate.
Also heard as
- bimetallic strip
- thermostatic bimetal
Related terms
Cold roll
To pass metal through rollers at ambient temperature to reduce its thickness and increase its strength.
Duplex
A metallurgical structure consisting of a roughly equal mixture of two distinct phases.
Alloyant
An element or material added to a base metal to modify its physical or chemical properties.