Sesceptor sheets are selected so that their magnetic permeability decreases to unity at approximately the desired operating temperature thereby limiting heating to this "Curie temperature" and providing substantial uniformity of temperature in the panel Preferably, the susceptor includes ...http://www.google.com.au/patents/US5808281?utm_source=gb-gplus-sharePatent US5808281 - Multilayer susceptors for achieving thermal uniformity in induction processing of organic matrix composites or metals 
