"Interface ferromagnetic disk" meaning "round piece of any metal efficiently heated by induction".
I think this downside of induction is wildly overstated; I have very few pieces of cookware that aren't "induction compatible", and I certainly didn't shop for them with that as a criteria. Any All-Clad pan works; my cheap-o omelette pan works; my enameled dutch oven works; obviously, my cast iron skillet works.
So much normal, good cookware works on an induction cooktop that it might make more sense to think about "induction incompatibility" as a liability of exotic (or particularly cheap) cookware, instead of a liability of induction.
I think this downside of induction is wildly overstated; I have very few pieces of cookware that aren't "induction compatible", and I certainly didn't shop for them with that as a criteria. Any All-Clad pan works; my cheap-o omelette pan works; my enameled dutch oven works; obviously, my cast iron skillet works.
So much normal, good cookware works on an induction cooktop that it might make more sense to think about "induction incompatibility" as a liability of exotic (or particularly cheap) cookware, instead of a liability of induction.