采用水热电泳沉积法在C/C-SiC复合材料表面制备了不同相组成的硅酸钇复合抗氧化外涂层.采用X射线衍射仪(XRD)和扫描电子显微镜(SEM)对涂层的相组成和显微结构进行了表征.研究了不同相组成对硅酸钇涂层的显微结构和抗氧化性能的影响.结果表明,Y_2SiO_5和Y_2Si_2O_7两相配比对涂层的显微结构和抗氧化性能有较大的影响.随着复合涂层中Y_2Si_2O_7含量的增加,复合硅酸钇外涂层的热膨胀系数逐渐接近于SiC内涂层的热膨胀系数.当组成达到m(Y_2SiO_5)/m(Y_2Si_2O_7)=3:7时,内外涂层的热膨胀系数最为接近,从而得到均匀、致密、无显微裂纹、抗氧化性能优异的复合硅酸钇涂层.该涂层在1773K静态空气中,经过氧化100h后,失重仅为1.2%;继续增加Y_2Si_2O_7含量,内外涂层的热膨胀系数差异逐渐增大,涂层再次出现裂纹,抗氧化性能随之下降.
Yttrium silicates composite oxidation resistant coatings with different phase compositions were deposited on SiC-C/C composites surface by a hydrothermal electrophoretic deposition process. The phase compositions and microstructures of coatings were analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The influence of phase compositions on the microstructure and oxidation resistance of yttrium silicates coatings were particularly investigated. Results show that Y_2SiO_5/Y_2Si_2O_7 ratio has strongly influence on the microstructure and oxidation resistant performance of yttrium silicates coatings.With the increace of Y2Si207 content, CTE of yttrium silicates coatings are closed to that of SiC bonding layer. When the mass ratio of Y_2SiO_5/Y_2Si_2O_7 reaches 3:7, dense and uniform yttrium silicates coatings with perfect oxidation resistance are achieved. After l00h oxidation in 1773K, weight loss of the coated C/C composites is only 1. 2%. While increase Y_2Si_2O_7 content continuely, the difference of CTE between inside and outside coatings increaces, which will result in cracked coatings and the decrease of oxidation resistance.
参考文献
| [1] | 黄剑锋,李贺军,熊信柏,曾燮榕,李克智,付业伟,黄敏.炭/炭复合材料高温抗氧化涂层的研究进展[J].新型炭材料,2005(04):373-379. |
| [2] | 李贺军.炭/炭复合材料[J].新型炭材料,2001(02):79-80. |
| [3] | Huang J F;Zeng X R;Li H J et al.[J].Journal of Materials Science,2004,39(24):7383-7385. |
| [4] | Jian-Feng Huang;He-Jim Li;Xie-Rong Zeng .Yttrium silicate oxidation protective coating for SiC coated carbon/carbon composites[J].CERAMICS INTERNATIONAL,2006(4):417-421. |
| [5] | Webster J D;Westwood M E;Hayes M F H et al.[J].Journal of the European Ceramic Society,1998,18(16):2345-2350. |
| [6] | Huang J F;Zeng X R;Li H J.ZrO2-SiO2 Gradient Anti-oxidation Coating for SiC Coated Carbon/carbon Composites by The Sol-gel Process[A].,2003 |
| [7] | Koichiro Fukuda;Hiroyuki Matsubara .Thermal Expansion of δ-Yttrium Disilicate[J].Journal of the American Ceramic Society,2004(1):89-92. |
| [8] | Yuzuru Ogura;Masayuki Kondo;Tatsuo Morimoto .Oxygen Permeability of Y_2SiO_5[J].Materials transactions,2001(6):1124-1130. |
| [9] | 黄剑锋,邓飞,曹丽云,吴建鹏,贺海燕,葛明辉.声化学法可控合成硅酸钇纳米晶[J].人工晶体学报,2007(02):464-466. |
| [10] | Huang J F;Zeng X R;Li H J et al.[J].CARBON,2003,41(10):2825-2829. |
| [11] | Mario A;Alicia D .[J].Journal of the American Ceramic Society,2000,86(06):1 351-1 355. |
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