Electromagnetic compression was integrated into the process chain of hot metal extrusionin order to reduce the cross section of the workpiece locally. To integrate both processes,a tool coil for electro-magnetic compression is positioned behind the die exit and coaxiallyto the extrudate. Additionally, a counter die in the shape of a mandrel can be mounted tothe mandrel of a porthole extrusion die, which extends into the working area of the toolcoil. Experiments were conducted on hollow profiles which were compressed byelectromagnetic forming subsequent to extrusion. Due to an extremely short processingtime of the high speed forming process, a compensation of the relative speed between theworkpiece and the tooling can be ignored. For determine the workpiece displacementduring the electromagnetic forming process, a new measuring strategy based on thePhoton Doppler Velocimetry was developed.
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