Conductive heating of bent metallic pieces using alternating current leads to high temperature differences between inner and outer radii due to different current densities. Technical solutions for homogenisation of these temperatures cannot always be adapted to industrial series production - partly because of missing process stability or flexibility – or do not provide the required quality in a short enough cycle time.
However, specially developed water-cooled magnetic field concentrators directly influence the amount of heat generated in the curves and can be easily used in mass production. Temperature inhomogeneities are decreased, which is important for temperature-sensitive applications like hardening or annealing.