Magnetic flux control in induction systems

Magnetic flux controllers are widely used in induction heating systems for concentration, shielding or redistribution of the magnetic field which generates power in the part to be heated. Controllers, made of Soft Magnetic Composites (SMC), provide accurate heat pattern control, improve parameters of inductors and performance of the entire installation. In melting systems, especially in the case of vacuum furnaces, cold crucible and other specialty furnaces, the magnetic control can provide large energy savings, magnetic field shielding, shorter melting cycles and optimized field distribution for enhancement of the metallurgical processes. Due to the diversity of applications, service conditions of controllers are very different including very severe cases. Mechanical, magnetic, electrical, thermal and other properties must be considered in design and application of SMC. This article describes properties and performance of SMC typically used in induction heating technology. Several presented case stories are based on more than 20 years of R&D and practical experience of scientists and practitioners at Fluxtrol, Inc. Presented material may be interesting not only for induction heating community but also for all people using AC magnetic fields in technological processes.