Titre : |
Thermal analysis and modification of C/C ablative composites for high-temperature insulation applications |
Type de document : |
texte imprimé |
Auteurs : |
Hamed A. Al-Falahi, Auteur |
Année de publication : |
2023 |
Article en page(s) : |
p. 379-391 |
Note générale : |
Bibliogr. |
Langues : |
Anglais (eng) |
Catégories : |
Analyse thermique Caractérisation Composites à fibres de carbone Graphitisation Hautes températures Isolants thermiques Isolation thermique Phénoplastes
|
Index. décimale : |
668.4 Plastiques, vinyles |
Résumé : |
This study focuses on the modification and thermal analysis of eight distinct carbon-carbon (C/C) composite types, designed as advanced thermal insulators. The investigation proceeded along two primary pathways. Firstly, an examination was conducted on the impact of phenolic resin modification, aimed at diminishing the erosion rate of these composites when exposed to an oxyacetylene flame. This involved integrating ammonia molecules with nickel ions in a complex, facilitating hydrogen-oxygen bonding, as evidenced by the pronounced broad band of hydroxyl (OH) groups in Fourier-transform infrared spectroscopy (FTIR) results. The presence of this nickel complex was observed to accelerate the graphitization level (GL). Secondly, a comprehensive thermo-mathematical analysis was undertaken on C/C models subjected to oxy-acetylene flames, utilizing the Finite Element Method (FEM) as simulated via the ANSYS software package. X-ray diffraction analysis conducted at 1650℃ revealed the presence of both graphite and turbostratic structures, designated as T&G. This signifies an enhanced GL in resins modified with 10 wt.% of the nickel complex Ni(CH2COCH2COCH3)2.2NH3, compared to those with 3 and 5 wt.% modifications. The effectiveness of modified C/C composites was found to be contingent on the specific type of additive and reinforcement used. Furthermore, a notable convergence between practical and mathematical analysis results was observed, establishing a reliable database for optimizing the selection of insulation type and thickness in practical applications. This investigation underscores the significance of chemical modifications in enhancing the thermal insulation properties of C/C composites. The findings hold substantial implications for the development of high-performance insulation materials, particularly in contexts demanding resistance to extreme temperatures and erosive environments. |
Note de contenu : |
- Experimental : Material and specimen preparation - Characterization of devices - Ablative test technique by oxy-acetylene flame
- Results and Discussion : Nickel complex effect on the graphitization level of novalac by oxy-acetylene flame - Spectroscopy characterization by FT.IR - Ablative properties of C/C phenolic composites at oxy-acetylene flame - Transient thermal analysis (experimental and theoretical) - Discuss practical and theoretical results
- Table 1 : Resin systems prepared
- Table 2 : Most reliable parameters at different concentrations
- Table 3 : The frequencies of non-modified and modified resin prepared (cm–1)
- Table 4 : Effect of type of filler on the ablative and physical properties under oxy-acetylene flame at 1650℃
- Table 5 : Material properties of composites under test
- Table 6 : Experimental and theoretical boundary conditions
- Table 7 : Ablative parameters for carbon cloth-phenolic composites (group A) at 10 mm thickness
- Table 8 : Ablative parameters for carbon cloth-phenolic composites (group A) at 10 mm thickness |
DOI : |
https://doi.org/10.18280/rcma.330605 |
En ligne : |
https://www.iieta.org/download/file/fid/115607 |
Format de la ressource électronique : |
Pdf |
Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=40766 |
in REVUE DES COMPOSITES ET DES MATERIAUX AVANCES > Vol. 33, N° 6 (12/2023) . - p. 379-391