为什么CST,HFSS基板材料磁导率增加后，仿真很慢？

Changed the catergory.
The permeability (or relative permeability) is the measurement of the ability of a material to support the formation of a magnetic field within itself. If you increase the permeability, in my opinion, you modify the material's property (increase the Q factor) that it can store more energy from the applied magnetic field. Therefore, it should take longer time for the material to radiate the stored energy into free space.
About verification, you may establish a RF resonance model, linearly increase the permittivity and/or permeability and I expect the following:
1. Q factor is increased.
2. Resonance frequencies moves toward lower frequency range.
3. Bandwidth becomes narrower.
4. Slover takes longer time to meet the numerical noise level.