Design and optimization of induction coil for improved temperature uniformity in fast heating of sheet metal

Abstract The application of induction heating technology in hot sheet metal forming processes allows for the design of resource-, and time-efficient processes due to its rapid heating rate and high energy efficiency. The major challenge hindering the broader use of induction heating in hot sheet metal forming is the in-plane temperature non-uniformity, particularly for fast heating rates. In this work, a new serial-parallel coil architecture was introduced to address the problem of temperature field uniformity in sheet metal heating processes. A simulation with a coupled magnetic and thermal interface was developed in COMSOL Multiphysics® and validated through experiments. The geometric parameters of the coil were studied numerically. The new coil design enables heating of X46Cr13 steel blank to over 1000 °C in 10 s, reducing the normalized standard deviation (NSD) in surface temperature from 27.06 to 2.03% compared to the conventional pancake coil. This paper demonstrates the potential of the new coil designed with an improved uniformity of the temperature field for sheet metal induction heating system.