The hardening process is pretty simple- - - -Heat the part until it's just barely red, roll it around in the powder to coat it pretty well, and heat again until the powder melts and flows evenly. Keep the heat going for a minute or two, but don't get the metal hot enough to melt it or change its shape. After about 2 minutes of moderate heating, quench the part in icewater. Clean up any residue, and do whatever polishing you choose to get a good surface finish. The part will have a hard surface several thousandths thick, but the center will still be tough and flexible, not brittle. The powder is basically carbon, which bonds to the surface of the metal and case-hardens it.
Jerry
