Changed oxidation behavior of ZrB2-SiC ceramics with the addition of ZrC

Oxidation behavior of ZrB2 SiC ceramics containing 0, 10 and 20 vol% ZrC was studied at 1600 degrees C in stagnant air. The structures of oxide scales depended on ZrC content. The thickness of the SiO2-rich glass layer on the outermost surface decreased steeply with the addition of a-C. One ZrC-corroded layer, containing ZrCxOy, SiC and ZrB2, was observed in ZrB2-SiC-ZrC. The oxidation kinetics was converted from parabolic to linear for the ceramics with 20 vol% ZrC. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.