Anisotropy oxidation of textured ZrB2-MoSi2 ceramics

Oxidation behavior of hot forged textured ZrB2-20 vol% MoSi2 ceramics with platelet ZrB2 grains was investigated at 1500 degrees C for exposure time from 0.5 to 12 h. Compared to untextured ceramics, the textured ceramics showed obvious anisotropic oxidation behavior and the surface normal to the hot forging pressure demonstrated better oxidation resistance. Such improvement in the oxidation resistance is primarily considered as a higher intrinsic ZrB2 atomic density on the orientated {0 0 l} planes in the textured ceramics. It is expectable that the anisotropic textured ZrB2-MoSi2 ceramics can offer better oxidation resistance when a certain surface with higher oxidation resistance is exposed to air at elevated temperature. (C) 2012 Elsevier Ltd. All rights reserved.