Rapid oxidation characterization of ultra-high temperature ceramics

Here, a novel method for testing ultra-high-temperature ceramics (UHTC) at a high temperature, rapidly, at a low cost is introduced. A self-supported, self-heated ribbon specimen is used with a table-top apparatus to achieve the necessary high temperatures. This method enables a large temperature-time-composition parameter space to be covered by rapidly producing a large set of postoxidation samples for analysis. The complex oxide scale known to form during oxidation of UHTC materials is shown to be easily reproduced using this method. A ZrB2-SiC (15 vol%) UHTC material was tested at 1700 degrees C for 15 min. The oxide scale consists of a thin outermost silica (SiO2) layer and a zirconia (ZrO2) columnar layer with small amounts of SiO2 embedded between the ZrO2 columns. A region of SiC-depleted zone was observed between the unreacted core and the ZrO2 layer. The measured thickness of the oxide scale was 102 mu m and similar to 120 mu m for the SiC-depleted zone.