高温气冷堆包覆燃料颗粒的化学气相沉积

我国正在建造１０ＭＷ高温气冷堆，包覆燃料颗粒的研制是高温气冷堆的关键技术之一。ＴＲＩＳＯ型包覆燃料颗粒是由燃料核芯、疏松热解碳层、内致密热解碳层、碳化硅层和外致密热解碳层组成。采用化学气相沉积方法，选用乙炔、丙烯、甲基三氯硅烷和氢气作为反应气体，在直径为５５ｍｍ锥形流化床包覆炉中制备包覆燃料颗粒。本文系统地研究了工艺参数和性能之间的关系，摸索出疏松热解碳层、致密热解碳层和碳化硅层的最佳包覆工艺条件，总结出经验公式，用扫描电镜观察了包覆燃料颗粒的微观结构，制备出满足设计要求的ＴＲＩＳＯ型包覆燃料颗粒。

Chemical vapor deposition of coated fuel particles for HTGR

The 10 MW high temperature gas cooled reactor(HTR 10) is currently under construction in China. The research and development of coated fuel particles is one of the most important part in the research work of the HTR 10. The TRISO type coated fuel particle consists of a microspheric fuel kernel surrounded by four layers: a porous pyrolytic carbon(PYC),an inner dense PYC, a pyrolytic silicon carbide and an outer dense PYC. The coated fuel particles were made in a 55mm diameter conical fluidized bed coating furnace by chemical vapor deposition, using acetylene,propylene,methyltrichlorosilane and hydrogen. The relationship between the coating parameter and the properties of the coated fuel particles have been systematically investigated. The optimum coating technology of porous PYC layer, dense PYC layer and SiC layer was obtained by controlling the deposition parameters according to the formula summarized from experiments. The microstructure of coated fuel particles was observed using SEM(scanning electron microscope). The TRISO type coated fuel particle with the properties fulfilling the design specification has been steady fabricated.