A fused glass coating for oxidation protection of Mo-W-ZrO2 cermet

作者：Zhang Jiu^*; Mei Guohui; Zhao Shumao; Meng Hongji; Xie Zhi

来源：Surface and Coatings Technology, 2015, 261: 189-194.

DOI：10.1016/j.surfcoat.2014.11.036

• Mo-W-ZrO2 cermet
• Anti-oxidation coating
• Borosilicate glass
• Fusing

Mo-W-ZrO2 cermet is suitably used for the liquid steel temperature sensor due to its excellent erosion resistance, good thermal shock resistance and high-temperature strength. However, it is easily oxidized in the firing process of the sensor below 1000 degrees C, which limits its application. In this work, a continuous coating of borosilicate glass was developed to prevent the cermet from oxidizing by a two-step process. Raw materials of borax and potash feldspar were initially fused at 1200 degrees C and ground into powder. Then, the slurry of the powder and ethyl alcohol was applied to the cermet and fused at 1000 degrees C. Results showed that the coating had an amorphous nature and low volatility (0.39% weight loss up to 1000 degrees C), which exhibited good continuity and adhesion to the cermet Moreover, no matter whether the coating was in a non-molten or molten state (800 or 1000 degrees C), it had good oxidation resistance. According to the application test in the firing, the coating could protect the cermet from oxidation at 400-1000 degrees C. The method of fused glass coating may have important implications for other oxidation resistance in a wide temperature range, especially at low temperatures.

• 出版日期2015-1-15
• 单位东北大学