What are the challenges in synthesizing hafnium-modified sicn fibers?
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The challenges in synthesizing hafnium-modified SiCN fibers include the need to carefully control the reaction pathways of hafnium alkoxide with different precursors, such as cyclotrisilazane and polysilazane, to achieve desired microstructures. Additionally, the distribution of hafnium within the ceramic network significantly impacts the high-temperature behavior, with different distributions leading to varying thermal stabilities and decomposition tendencies. Furthermore, the addition of hafnium to polysilazane-based composites results in enhanced thermal stability, while local enrichment of hafnium in cyclotrisilazane-based samples can induce pronounced decomposition at elevated temperatures. These challenges highlight the importance of precursor chemistry and architecture in determining the properties and performance of hafnium-modified SiCN fibers.
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| Papers (5) | Insight |
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Open access•Dissertation 01 Jan 2016 9 Citations | Not addressed in the paper. |
1 Citations | Not addressed in the paper. |
09 Sep 2015 19 Citations | Not addressed in the paper. |
| Challenges in synthesizing hafnium-modified SiCN fibers include achieving high tensile strength and stability, as demonstrated by the study on Si(Hf)CN/CF composites with promising results up to 1500°C. | |
63 Citations | The challenges in synthesizing hafnium-modified SiCN fibers include the crucial influence of polymer architecture on microstructural evolution, leading to varied high-temperature behaviors and distribution of hafnium. |
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