Technical ceramics for induction technology

 

Induction technology makes use of a particular property of ceramic materials. As a rule, ceramics are not electrically conductive and are non-magnetic. An induction field therefore has no effect on ceramic components and thus also does not cause any heating. This allows the effect of the energy to be controlled with precision. Avoiding unnecessary heating permits cost savings and reduces the thermal stresses on the equipment / tools.

Silicon nitride, which is wear-resistant, electrically insulating and non-magnetic, is used in many applications. In addition, silicon nitride is characterised by a very good resistance to temperature change. Depending on the application in question, aluminium oxide and zirconium oxide are also highly suitable.

  • Welding rollers made of silicon nitride are used in plants for the production of pipes made from coil in order to fix the seam flanks during the longitudinal welding. Ceramic welding rollers do not influence the welding process with induction and electric arc welding since they are non-magnetic and electrically insulating.
  • Workpiece holders made of ceramics are used as holders during induction hardening. The components which are to be hardened are heated inductively without the ceramics interfering with the induction field. The components are then quenched. These enormous temperature changes do not affect the ceramics, they continue to function durably.

Sliding shoe/sliding block: Ceramic sliding blocks are frequently used in induction hardening plants. In hardening plants for crankshafts for example, the components which are to be hardened run on the surface of the ceramics. Since silicon nitride retains its strength and resistance to wear even at very high temperatures, it is outstandingly suitable for this application.