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Title:: Self Healing Oxidation Resistance of C/C Composite Covering a Broader Temperatures Range

Author(s):: ZHANG Weigang; (State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China)

摘要:: 在前期碳材料自愈合抗氧化研究的基礎上，提出了通過多元陶瓷基體改性賦予碳/碳復合材料在較寬溫度范圍內實現自愈合抗氧化的基本原理和技術方案，分析了B4CSiC、ZrCSiC和ZrB2ZrCSiC等多元陶瓷的抗氧化機理，并采用新近合成的ZrB2ZrCSiC三元復相陶瓷有機前驅體，通過PIP技術制備了一系列超高溫復相陶瓷改性的碳/碳復合材料，研究了該類復合材料在2 200 ℃以下高速氣流沖蝕環境中的協同抗氧化和抗燒蝕性能，發現材料表面生成的復合氧化物層能夠在一定條件下賦予復合材料自愈合抗氧化能力。

Abstract:: Mechanism of selfhealing oxidation resistance and preparation technique of a kind of carbon fiber reinforced pyrolytic carbon composite (C/C) are suggested in the study. The composite characterized with homogeneous nanodispersed complex matrix of ZrB2ZrCSiC was prepared by polymer impregnanting and pyrolysis (PIP) process, ie the nanodispersed ZrB2ZrCSiC composite ceramics were introduced into a porous C/C composites with low density using complex precursors prepared by completely dissolving of ZrB2, ZrC polymeric precursors and polycarbosilanes in dimethylbenzene solution. Ultrahigh temperature ablation tests shown that the linear and mass ablation rate at 2 200 ℃ for the C/CZrB2ZrCSiC composites decreased by 858% and 710%, respectively, in comparison with those of C/CSiC composites. The very low ablation rates result from the formation of uniformly distributed ZrO2SiO2 continuous glass coating, which prevented the molecular innerdiffusion of oxygen and thereby protected the carbon phase from being further oxidized.