VakuumInduktionsschmelzen

VakuumInduktio, or Vacuum Induction, is a method of heating conductive materials by means of an alternating magnetic field within a vacuum chamber. It is used primarily in metal processing to achieve thermal treatments without exposure to reactive gases.

The technique uses an induction coil driven by an AC power source; the alternating field induces eddy currents in the workpiece, heating it through resistive losses. In a vacuum, heat transfer from the hot surface occurs mainly through radiation and conduction to fixtures, as convection is negligible. The lack of atmospheric gases reduces oxidation and contamination, enabling high-purity processing and the ability to heat at higher temperatures without scale formation.

Typical implementations are vacuum induction furnaces or vacuum induction heaters used for annealing, brazing, soldering, sintering, and preheating for diffusion bonding or powder compaction. Material selection includes steels, nickel-base alloys, superalloys, and ceramics that are vacuum-stable.

Advantages include reduced oxidation, cleaner surface finishes, faster heating cycles, and better control over atmosphere. Limitations involve higher equipment costs, complexity of vacuum systems, potential material outgassing, and constraints on geometry and heating depth due to skin effect and frequency. The approach is established in industrial heat treatment and materials research as a way to combine induction heating with a controlled, inert environment.