abstract
This work main goal is to develop metal composites on a ceramic matrix, designated as CERMETs. Hence, and having as starting materials the ceramic and composite powders produced by INNOVNANO, mechanosynthesis powders were also prepared. The yttria stabilized zirconia (YSZ) based powders (produced by those two methods) were crystallographic, chemically, morphologically, rheological, thermal and magnetically characterized. Pressed compacts from the previous powders were prepared and sintered in vacuum conditions, followed by their characterization namely in terms of structure, microstructure, mechanical and magnetic behavior. The results were analyzed with a critical mind, trying to co-relate the physical and chemical properties of the powders and green compacts with the final sintered properties. The comparison between ceramic and composites (either powders, either sintered compacts) was always the main goal during the development of this work. The results include the evaluation of the meaning and importance of the several powders preparation steps that are conducted in INNOVNANO’s producing method, the importance of the tetragonal zirconia phase stabilization, the magnetic response and the interpretation of the decrease in mechanical resistance verified in CERMETs.
authors
Ricardo Serrazina
our authors
supervisors
Paula Vilarinho, Ana Senos, Rosa Calinas, Nuno Neves