Hi David,
No — the Vector Potential solver has no B-H curve input. A magnetic material there is a relative permeability and a conductivity, and that's all it can do: no saturation, hysteresis or remanence in the low-frequency solvers. (FDTD has further magnetic models for dispersive media, but they're linear too.) Nonlinear magnetic materials have been on our development list for a while, but they have not been implemented yet.
For your case I'd suggest the chain from your other thread: solve coil and core with the vector potential solver (lossless, so no tissues in that simulation) and feed the resulting A into the magneto-quasi-static solver on the head model to get the induced E-field. The LF tutorial "Wireless Power Transfer: Exposure Assessment" works exactly like this.
You can handle saturation approximately by iterating the permeability. Solve once with the datasheet mu_r, extract B in the core, read the manufacturer B-H curve at that point, set the secant value mu_r = B/(mu0*H) and re-solve. Two or three passes should already converge quite well. Only the vector potential simulation involves mu, so that's the only one you would iterate. Note that B might be strongly non-uniform in the ferrite core, so a single uniform mu_r would average quite different local operating points. Splitting the core into two or three bodies (poles, yoke, the rest) and iterating each separately might be a good enough approximation, depending on your application.
What this approximation gives you is saturation, not hysteresis: no minor loops, and nothing about core losses or the falling edge of the pulse. Also, ferrite mu depends on frequency as well as on B, and the solver applies one value at one frequency; take mu from the datasheet at a frequency representative of your pulse rise time rather than at DC.
Everything above is scriptable (setup the two linked simulations in the GUI, then use To-Python to generate a good starting point for your scripts).
Sweeping should work fine, even for linked simulations. Let me know if you have issues getting that to work!
Best regards,
Sylvain