Effect of Surface Oxidation at 1500 °C on Flexural Strength and Thermal Shock Resistance of the ZrB₂-SiC-ZrC Ceramic

Abstract:

The isothermal oxidation of the ZrB₂-SiC-ZrC ceramic was carried out in static air at a constant temperature of 1500±15 oC for 20 min. Compared with the original strength of 580 MPa, the strength of the oxidized specimen increased to 655±45 MPa, because the flaws in the surface of the specimen were sealed by the oxide layer. The thermal shock resistance of the specimens before and after the oxidation was measured by the water quenching. The measured ΔT_crit for the oxidized specimen was 641 oC that was obviously greater than 348 °C for the unoxidized specimen. The improvement in the thermal shock resistance was attributed to the formation the oxide layer on the surface of the specimen. The results here pointed to a promising method for improving strength and thermal shock resistance of ZrB₂-based ceramics.

• Periodical: Advanced Materials Research (Volumes 712-715)
• Pages: 115-118
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.712-715.115
• Online since: June 2013
• Authors: Min Wang, Zhi Wang, Shi Chao Li, Jian Zhang, Bao Shuai Zhang
• Keywords: Oxidation, Strength, Thermal Shock Resistance, ZrB₂-Based Ceramic

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