Multifunctional Si3N4/(beta-SiAlON+TiN) layered composites

Layered multifunctional ceramic composites on the base of Si3N4 and TiN hav e been prepared by tape casting. The reaction conditions for in situ prepar ation of beta-SiAlON + TiN composite were optimised and dense Si3N4/(beta-S iAlON + TiN) layered materials were prepared by hot pressing. The bending s trength and fracture toughness of layered materials measured in the directi on perpendicular to the layer alignment were remarkably higher (1184 MPa an d 9.75 MPa m(1/2)) in comparison to the "monolithic" beta-SiAlON + TIN comp osite (647 MPa and 4.71 MPa m(1/2)). High anisotropy was achieved for the e lectrical resistance of the layered materials in parallel (6.10(-2) Omega c m) and perpendicular (5x10(11) Omega cm) direction to the layer alignment. (C) 2000 Elsevier Science Ltd. All rights reserved.