ZrB2-SiC(Al) ceramics with high resistance to oxidation at 1500 °C

In this paper, we study the oxidation behaviour of a ZrB2/Al-doped SiC composite at 1500 degrees C. The composite was prepared by hot-pressing the mixture of ZrB2 and polymer-derived SiC(Al). The oxidation behaviour was studied by measuring the weight change as a function of oxidation time and by observing the structure of the oxide layer. It is shown that the ZrB2-SiC(Al) exhibits different oxidation behaviour and improved oxidation resistance as compared to the conventional ZrB2-SiC without Al-doping. The improvement in oxidation resistance is attributed to that AI-doping could increase the bond strength of the Si-O and suppress the active oxidation of SiC. (C) 2013 Elsevier Ltd. All rights reserved.