Induction Hardening
Induction hardening has considerable advantages compared to other surface hardening processes. The heat is only generated where it is functionally needed: In the surface layer. The high-precision process thus causes fewer distortions, enables process data acquisition at part level thanks to single-work-piece-flow and at the same time consumes significantly less energy than case hardening or flame hardening processes. Powered by green electricity, induction hardening enables CO2 emission-free production.
How does induction hardening work?
Electromagnetic induction plays a key role in induction hardening. An inductor (copper coil) is placed around the workpiece to be processed, which selectively heats the metal to be processed. This is done by generating an alternating voltage at the inductor. This electrical voltage induces eddy currents that selectively heat the material through its electrical resistance. The penetration depth of the induction depends on the frequency of the alternating voltage - the higher the frequency of the voltage, the less deeply the heat penetrates the workpiece. The energy source must be adapted to the respective requirements so that the frequency is optimised for the desired hardening pattern. To prevent the workpiece from heating through completely, the duration of the alternating current supply is limited to a few seconds during induction hardening. This avoids excessive temperature differences that could have a negative effect on the material being processed. As the workpieces are quenched with water immediately after hardening, the steel is also protected against distortion.
Induction hardening 2.0 - the SDF® process from eldec
With Simultaneous Dual Frequency, also known as SDF®, eldec offers a very special hardening process that is primarily used for complex workpiece geometries. A medium frequency is superimposed on a high frequency so that both frequencies act on the component at the same time. This technology ensures that certain areas of gears, for example, are heated evenly even though they are at different distances from the inductor. With SDF® hardening, a surface can reach the required temperature at the tooth root and tooth tip so that the entire workpiece is hardened true to contour. The result: absolute precision, uniform depth and temperature level.
