Functionally graded materials made by water-based multilayer technology

The development of Functionally Graded Materials (FGM) with graded microstructures concerning composition or porosity opens new fields of application. Components with different porosities combine different properties in the gradient structure regarding thermal conductivity and capacity, density, mechanical strength and elastic modulus. Graded microstructures result in innovative, multi-functional properties combinations, such as hard and ductile, electrically or thermally conductive and insulating, magnetic and nonmagnetic for metal-ceramic composites. The ceramic multilayer technology allows the production of FGM with a high value concerning the degrees of freedom for the designing of FGM. The possibilities of the multilayer technologies were demonstrated by the water-based production of multilayers with graded density (Ca-aluminate/Al2O3). Technologies were developed for the production of ceramic platelets as well as the modification of the connection between the different. SEM-images of cross-sections of the sintered components and of fractured surfaces of tested samples show the different connection between the single layers within the sintered structures as well as the crack propagation.