Temperatures calculated but thermal expansion calculation is missing ?

I generate a quite simple 3-D model:
A cylinder made of copper with a radius of 0.2m and a height of 0.5m and heated at its mantle with a total energy of 1000 Watts for one hour. Within this cylinder included in the center, there is another cylinder made of titanium with a radius of 0.1m and a length of 0.3m.

I apply the physics:
- Heat transfer in solids and
- solid mechanics

A "Multiphysics" node is generated automaticely.
I choose "temperature coupling"

I generate a normal sized mesh and calculate
a time dependend study with 10 sec steps for one hour.

I get a reasonal temperature distribution from the calculation.
But I'm surpised, that the elastic strain energy density (solid.Ws (J/m^3)) and all other parameters like (solid.ep1) of the solid mechanics are exactly zero, without any decimals. As there is a temperature difference of 5K and the thermal expansion coefficients of the material differ by 10 exp(-5) I would expect some stress.

My impression is, there is no mechanics calculated.

Any ideas, what I might have missed?