Abstract
SiC and W-Al-Si oxidation resistant coatings on carbon-carbon(C/C) composites surface were prepared by pack cementation and slurry method. The phases, microstructure of the SiC and W-Al-Si coatings were studied by XRD and SEM. The oxidation resistance of mono-layer SiC and double-layer SiC/W-Al-Si coatings were also tested by isothermal oxidation test at 1773 K in air, respectively. The results show that the mono-layer SiC coatings composed of Si and SiC only can protect C/C composites for several hours from oxidation at 1773 K because of its porous structure. WSi2 and W(Si, Al)2 are two main phases of the outer W-Al-Si layer. The anti-oxidation property of the double-layer SiC/W-Al-Si coatings with a approximately 100 μm thickness is superior to that of the mono-layer SiC coatings, and the mass loss of SiC/W-Al-Si coated C/C composites is less than 5% after oxidation at 1773 K in air for 19 h. By optimization of the slurry ratio of W-Al-Si, the oxidation resistance of double-layer SiC/W-Al-Si coatings can be improved to over 19 h at 1773 K due to the elimination of penetrating crack created by dismatch between inner SiC and outer layer W-Al-Si for SiC/W-Al-Si coatings.
| Original language | English |
|---|---|
| Pages (from-to) | 17-20 |
| Number of pages | 4 |
| Journal | Cailiao Rechuli Xuebao/Transactions of Materials and Heat Treatment |
| Volume | 32 |
| Issue number | 7 |
| State | Published - Jul 2011 |
Keywords
- Carbon-carbon composites(C/C)
- Coatings
- Oxidation
- SiC/W-Al-Si