Transient FEM analysis
Background
Creating the model
Starting with a blank FreeCAD project, we build our bimetal strip in the Part workbench: First, draw a Cube Solid and rename it to “aluminium”. Give it the dimensions 100 x 10 x 2 mm (length x width x height). Create a second Cube Solid “steel” with the same dimensions and offset it 2 mm along the z-axis (via Placement > Position > z). Select both solids (using the Shift key and your mouse) and create Boolean Fragments from them. Rename the Boolean Fragments object to “bimetal strip” and in the data panel, change the mode from “Standard” to “CompSolid”. (It should also work by using the Union command instead of Boolean Fragments, however, with more complex intersecting shapes, there might be trouble with the FEM analysis later. So, better get used to using Boolean Fragments in the first place.) The result should look like this: