About the AC/DC and Nonlinear Magnetic Material Databases
For detailed information about Materials including the AC/DC Material Libary and Nonlinear Magnetic Materials Library, see the COMSOL Multiphysics Reference Manual.
Nonlinear magnetic materials are generally provided as interpolation functions for the magnetization curve without hysteresis effects. In the main equation nodes, that is in any of the nodes; Ampère’s Law, Ampère’s Law and Current Conservation, Faraday’s Law, or Magnetic Flux Conservation and, depending on which of the AC/DC interfaces is being used, one needs to select the magnetic field constitutive relation B-H curve or H-B curve.
For an example of the AC/DC materials database and of using nonlinear magnetic materials in general, see Small-Signal Analysis of an Inductor: Application Library path ACDC_Module/Inductive_Devices_and_Coils/small_signal_analysis_of_inductor