All of the DIY induction heating projects I have seen tackle the entire power supply from scratch (including voltage and current regulation). My goal is to take advantage of my Harbor Freight 80A inverter constant-current DC stick welder as the power source. This means that the hard part will be inverting the high-current DC to high-current high-frequency AC useful for magnetic-induction heating.
I will use the IRS2453DPBF-ND N-MOSFET H-bridge driver chip from IR to drive the high-current IRFP4310ZPBF-ND N-MOSFETS. My initial approach was to use a LM555CNFS-ND timer chip, a center-tapped work coil, and a 497-3110-ND MOSFET for inverting logic. However, the work coil will not have to be center-tapped if I use the H-bridge driver chip, which should result in better heating. If used motor oil turns out to be non-conductive, I will use it in a heat exchanger that pumps oil through the work coil. The work coil will be insulated from the crucible by refractory cement.
