Zpracování a vlastnosti keramické matrice s přidáním uhlíkových nanotrubic

Abstract

The aim of this work is to optimize the preparation conditions of the SiC composite with the addition of carbon nanotubes. The carbon nanotubes (CNT) were sprayed on the surface of submicron SiC powder with the CVD method by the thermal decomposition of C2H2. Iron was used as a catalyst for the creation of carbon nanotubes. A homogeneous distribution of Fe nanoparticles on the surface of SiC has being reached by grinding the SiC powder using steel grinding bodies or by precipitation of colloidal particles from an aqueous solution in the form of hematite (-Fe2O3). As sintering additives were used Y2O3 (14,2 wt%) and AlN (0,6 wt%). The densification of the materials was achieved by hot pressing the starting mixtures, which after the addition of the CNT, were washed in hydrochloric acid to remove the iron. On the prepared dense samples were observed the changes in the microstructure and their influence on the mechanical properties (KIC, HV).