Abstract
A SiCN/borosilicate glass anti-oxidation coating with double-layer structure was designed for C/C aircraft brake materials. The SiCN layer was introduced as transition layer to improve the wettability between borosilicate glass and C/C composites, and the microstructure results indicated that the coating with SiCN inner layer was dense and uniform. The oxidation resistance evaluation of the coated samples was conducted at 800 °C in air for 10 h. The weight loss of SiCN/borosilicate glass coated samples valued ~ 5.66% indicated that the oxidation resistant property of the simple SiCN/borosilicate glass coating was not good, which was mainly due to the relative large viscosity of borosilicate glass at 800 °C. B4C was introduced to add into the outer glass coating to improve the self-healing ability of the coating. After oxidized at 800 °C in air for 10 h, the weight loss of the SiCN/borosilicate glass-B4C coated samples was ~ 2.48%. B4C could consume the oxygen diffused into the coating and the reacted product B2O3 with a better fluidity at 800 °C could effectively heal cracks and pores in the coating to improve the oxidation resistance property. The reaction of B4C oxidized to B2O3 was accompanied with ~ 1.5 times volume expansion, which was also beneficial for the healing of defects.
Original language | English |
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Pages (from-to) | 175-182 |
Number of pages | 8 |
Journal | Ceramics International |
Volume | 44 |
Issue number | 1 |
DOIs | |
State | Published - Jan 2018 |
Keywords
- C. Anti-oxidation property
- D. BC
- D. Borosilicate glass
- E. C/C brake