Siebdruck von elektrisch leitfaehigen Keramiken zur Entwicklung heizbarer keramischer Mikrokomponenten

The objective of the current work was the development of electro-conductive ceramic screen printing pastes. By screen printing these pastes on ceramic substrates microstructured ceramic heating elements were developed, covering the temperature range from room temperature up to about 1000 C. Until now, no commercial pastes are available for this high temperature region. The scope of the work comprises the development of screen printing pastes of three different materials: Al_2O_3/TiN, Si_3N_4/TiN and Indium-Tin-Oxide (In_2_-_xSn_xO_3). The paste optimisation was conducted to accomplish the prerequisites for a dense sintered microstructure of the layers leading to reproducible electrical properties. Furthermore the rheological properties of the pastes were adjusted in order to yield an optimised printing result. Microstructured ceramic resistance heating elements, screen printed onto alumina substrates could be realized for the material combination Al_2O_3/TiN and for In_2_-_xSn_xO_3, whereas Si3N4/TiN showed severe deficiencies. Different types of heating elements were developed and examined with respect to their heating characteristics. It could be shown that the heaters can be operated up to temperatures of 1000 C. Potential applications for these devices are igniters, heating elements for sensors or for micro reaction technology components. Due to the linear temperature versus electrical resistance correlation they can also be used as temperature monitoring units. As a first application a heating concept for a ceramic microreactor was developed and built. The objective was a localized inductive heating of the reaction zone. It was possible to reach a temperature of 1000 C at the reaction zone, whereas the gas in- and outlet parts showed a temperature below 500 C. (orig.)SIGLEAvailable from TIB Hannover: ZA 5141(6906) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman