Casimir effect for conducting and permeable plates at finite temperature

The effect of temperature for the Casimir force is calculated for a system of two different parallel plates, one being a perfect conductor and the other infinitely permeable. The analysis of high and low temperature is developed via the behaviour of the Casimir free energy and entropy. In particular, in the case of high-temperature limit, it is shown that the repulsive character of the Casimir force between the plates is purely entropic.