About this Abstract |
| Meeting |
MS&T26: Materials Science & Technology
|
| Symposium
|
Molecular Approaches to Ceramics; Synthesis, Processing, Modeling, and Derived Ceramics
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| Presentation Title |
A Systematic Approach to Enhancing the Oxidation Resistance of C/C Composites Using Multi-Layer SiC–ZrB₂-Based Coatings |
| Author(s) |
Hema Ramsurn, Mosiur Rahaman, Mark Olima, Jacob McCormick, Michael Keller, Matthew Ryder, Sanwu Wang |
| On-Site Speaker (Planned) |
Hema Ramsurn |
| Abstract Scope |
This study evaluates oxidation resistance in carbon/carbon (C/C) composites coated with one- to six-layer SiC–ZrB₂-based architectures produced using pack cementation (PC), chemical vapor deposition (CVD), and slurry coatings. Oxidation tests at 1000 °C revealed that PC is an effective base layer, and boron addition (5B-PC) promotes formation of a stable B₂O₃–SiO₂ borosilicate glass, enhancing self-healing and oxide retention. Single- and double-layer systems failed quickly (<60 h) due to glass volatilization and crack formation. Multilayer designs incorporating both dense CVD barriers and reactive slurry layers show significantly improved durability, especially when slurry forms the outer layer. Five-layer structures maintain stability up to~400 h, while the optimized six-layer architecture (5B-PC+CVD+S+CVD+S+CVD) achieves exceptional oxidation resistance exceeding 500 h. SEM and EDS analysis confirmed oxidation confinement to the outer slurry layer, forming a dense SiO₂–ZrO₂ scale, while preserving inner CVD layers, demonstrating the critical role of layer sequencing and total coating thickness (600–700 µm). |