Thanks, yes i see that Saturation B is anywhere from 350mT to 1T, depending on the make of iron powder.
For some time now i have been trying to write a doc which calculates the CCM Boost PFC iron powder inductor for every different type, for a given inductance, for every different permeability torroid, and for every different type, and size, and for from 1 to 3 stacked torroids.........so as to see which solution is the cheapest and smallest, whilst still giving acceptable core losses and wind losses.
At the moment, i do an estimated guess at a torroid size in Sendust, then, after calculation, if its too small, i stack 2 and repeat, then if still too much loss i move to the next size up and repeat......quite a lot of calculations.
There is also something about micrometals "Bpk" actually meaning "Bpk/2"?....ie the "B" in the core loss equation of page 29 of the micrometals iron powder catalog is actually meaning Bpk/2?
Also, its a shame the "% of initial permeability" vs B doesnt graphs show below 90% for most of the iron powder types