Multiphysics modelling of magnetic Curie point materials: Application to thermal self-regulation during induction heating

Controlled Curie point materials are considered innovative due to their property of abrupt magnetic extinction when their temperature exceeds a specific threshold. This property could be used to make them very suitable for a variety of industrial processes that require temperature self-regulation. The use of these materials in magnetic induction heating may allow the power transfer to be greatly reduced at the Curie point, ensuring precise control of the heating process. However, recent developments have enabled the design of customisable materials, where the Curie threshold can be precisely adjusted during the manufacturing process in a range from ambient temperature to several hundred degrees. This tunability is commonly achieved in FeNi-based alloys, where the Curie temperature is controlled by adjusting the composition ratio of nickel and iron. Other alloying elements, such as aluminium or rare earth metals, can also be incorporated to further modify the magnetic and thermal properties. Therefore, designers need modelling tools to handle these phenomena. In this paper, a two-dimensional coupled electromagnetic and thermal model for the induction heating of magnetic materials with a low Curie point temperature is developed to validate the proof of concept.