沉积电压对水热电泳沉积硅酸钇涂层显微结构的影响

Influence of Deposition Voltage on Microstructure of Yttrium Silicates Coatings Prepared by Hydrothermal Electrophoretic Deposition Process

采用水热电泳沉积法在SiC-C/C复合材料SiC内涂层表面制备了硅酸钇抗氧化外涂层,并借助X射线衍射(XRD)、扫描电子显微镜(SEM)对涂层的相组成及显微结构进行了表征。讨论了沉积电压对硅酸钇涂层沉积量及显微结构的影响,并研究了不同沉积电压下涂层沉积量与时间的关系,同时测试了涂层试样的抗氧化性能。研究结果表明,随着沉积电压的升高,涂层的沉积量有所增加,涂层的致密性和均匀性也逐渐得到改善。当电压为210V时达到最佳,继续升高沉积电压,涂层的均匀性变差,当沉积电压为240V时,涂层出现明显开裂;不同沉积电压下涂层沉积量随时间呈抛物线变化;涂层在1500℃静态空气中经过10h氧化后,失重仍然小于2%。

Yttrium silicates oxidation resistance coatings are deposited on SiC-C/C composites surface by a hydrothermal electrophoretic deposition process. The microstructure of coatings is analyzed by scanning electron microscopy （SEM）. The influence of deposition voltage on the yttrium silicates coatings and the deposition amount of coatings is particularly investigated and isothermal oxidation performances of coating are tested. Results show that with the increase of deposition voltage, the deposition amount of coatings incareases, the density and uniformity of the coating surface are improved. When the deposition voltage reaches 210V, dense yttrium silicates coatings are achieved. While increasing the deposition voltage continuely, the uniformity of coatings decrease when the deposition voltage reaches 240V, high deposition voltage will result in cracked coatings. There is a parabola relationship between the deposition amount of coatings and time. After 10h oxidation, weight loss of SiC-C/C-yttrium silicates coating is less than 2%.