【摘 要】
：
Fibers degradation and matrix cracks are very common during fabrication of composites,which seri-ously reduces the reliability and properties of the composites.In this work,2D-Cf/ZrB2-SiC composites were fabricated by a joint processing of slurry infiltra
【机 构】
：
State Key Laboratory of High Performance Ceramics and Superfine Microstructure,Shanghai Institute of
论文部分内容阅读
Fibers degradation and matrix cracks are very common during fabrication of composites,which seri-ously reduces the reliability and properties of the composites.In this work,2D-Cf/ZrB2-SiC composites were fabricated by a joint processing of slurry infiltration and hot pressing.Based on thermal kinetics calculation,finite element simulation and detailed microstructure characterization,fibers degradation and matrix cracks formation mechanisms of the composites are discussed and revealed.Oxide impu-rities including SiO2 and ZrO2 react with carbon fibers,resulting in formation of ZrC,SiC particles and etching pits on the fibers,which also leads to a strong bonding between the fibers and matrix.On the other hand,thermal expansion mismatch between the fibers and matrix gives rise to serious thermal stress in the composites.The thermal stress distribution and development are analyzed by finite ele-ment simulation,which is in good agreement with the cracks\'formation in the composites.Based on the revealed microstructure evolution mechanisms,a potential solution to mitigate fibers degradation and matrix cracks is put forward.
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