| 摘要 |
A system for employing induction heating to heat a non-magnetic, electrically non-conductive material in situ quickly, uniformly, selectively and in a controlled fashion. Particles (4) which are essential to the improved use of induction heating for this type of application are added to the host material (6) and exposed to high frequency alternating electromagnetic fields such as those produced in an induction coil. The particles are ferromagnetic, having high magnetic permeability and high electrical conductivity. . The heat-generating efficiency of these particles when exposed to alternating magnetic fields, permits a smaller volume fraction of these particles in the host material such that the desired properties of the article remain essentially unchanged. Overheating of the article may be prevented by selecting the particle Curie point such that the particle autoregulates at a temperature about equal to the temperature to which the article is to be heated. These particles preferably have the configuration of a flake, i.e., a thin disk-like configuration. This configuration includes a first (x), second (y) and third (z) orthogonal dimension, wherein the first and second orthogonal dimensions (x, y) are each greater than the skin depth of the particle and are each at least about 5 times the third orthogonal dimension (z).
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