Abstract: The invention relates to an electrically and thermally conductive adhesive composition for cementing together at least one metallized (e.g. aluminized or silvered) surface of a positive temperature coefficient (PTC) element to at least one metallic (e.g. aluminum) electrode, in the manufacture of PTC thermistor devices which are potentially capable of operating in a working temperature range not less than ?55° C. to +300° C. and for at least 30,000 hours. The composition comprises, as the adhesive component, a curable silicone (e.g. silicone rubber) prepolymer, as well as finely divided silicon carbide and finely-divided silicon, and preferably also a finely-divided metallic powder.

Abstract: A method and system for fabricating electrical heating devices employing positive temperature coefficient (PTC) thermistor as heating elements which includes: assembling the heating devices with PTC thermistor heating elements preselected according to electrical resistance, applying pressure across the interface between the PTC heating elements and the radiator plates of the heating devices during their assembly, and exposing the heating devices for extended periods of time to both ambient and operational temperatures. The method of fabrication further includes continuously monitoring the electrical resistance of the heating devices and holding their electrical resistance stable by adjusting the pressure applied across the interface between the PTC heating elements and the radiator plates.

Abstract: An autoclave type sterilization device which includes an autoclave sterilization chamber with an electrical heating arrangement mounted thereon. This electrical heating arrangement employs one or more positive temperature coefficient (PTC) thermistors as heating elements. These heating elements are in direct thermal and electrical contact on opposing sides, which are coated with a conductive metal such as aluminum, with electrodes to supply electrical current. These electrodes are, in turn, in direct thermal contact on their outward-facing sides with respect to the heating elements with plates which are formed of a thermally conductive and electrically insulating ceramic material such as AL.sub.2 O.sub.3, and the plates are in direct thermal contact on their outward-facing sides with respect to the heating elements with heat radiation units which include heat transfer portions which are fabricated to engage and are in direct thermal contact with a portion of the wall of the autoclave chamber.

Abstract: An electrical heating device employing positive temperature coefficient (PTC) thermistors as heating elements, which provides direct contact between the thermistor heating elements and the radiation units on both sides with no intervening members and which also provides the electrical current to the heating elements via the radiation units.