You can reduce scaling during induction preheating of forging billets by using a protective atmosphere instead of heating in air, which results in significantly increased life of forging dies.
Preheating billet and bar forging stock in fuel combustion direct-flame furnaces results in significant metal loss through oxidation and scaling. It is possible to use a protective atmosphere in preheating forging stock using induction heating. Nitrogen, nitrogen-based atmospheres, argon and other atmospheres can be introduced into the inductor(s) to prevent or reduce oxidation and scaling of the material. Part 1 of this article (February 2005 Industrial Heating) discussed the protective atmosphere/induction heating installation, while results are discussed in this article.