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Polymer-derived ceramics (PDCs) which are fabricated through pyrolysis of preceramic polymers have attracted increasing attention due to their versatility in structure architecture design and property tailoring. Shaping at the polymer state using 3D printing allows the final ceramic products to exhibit arbitrary shapes and complex architectures that are otherwise impossible to achieve through traditional processing routes. The polymer-to-ceramic phase transition also provides additional space for mechanical property tailoring. A multiscale computational model is developed to explore the phase transition mechanisms and their correlations with processing parameters and failure response. Calculations in this work concern PMHS/DVB preceramic polymers. Molecular dynamics (MD) simulations are carried out first to track the atomic structure evolution at different temperatures. Continuum-scale ceramic phase formation is calculated on the basis of the competition between gas generation and gas diffusion. The effect of processing parameters on mechanical properties of pyrolyzed PMHS/DVB is systematically studied. Conclusions from this study can provide direct guidance for fabricating PDC composites with tailored mechanical properties.
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Energy Dissipation Pathway Control in Polymer Derived Ceramic (PDC) Composites
Ceramics are brittle due in large part to the limited availability of energy dissipation pathways when they are subjected to an impact load. The primary avenue for improving the material reliability and energy-absorption capability is to create new energy dissipation mechanisms that can be used to replace or minimize the kinetic energy associated with the debris shattering. In this paper, a computational framework is developed to investigate the relationship between phase composition and energy dissipation pathways in polymer derived ceramic (PDC) composites by accounting for the key processing parameters and deformation/failure mechanisms. It is found that the phase composition that promotes both the Mullins effect and the ligament bridging mechanism can significantly improve the structural integrity of the composite material. A fundamental understanding of how to redistribute the impact energy dissipation in a controllable path would hold great promise for fabricating PDC composites with tailored properties.
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- Award ID(s):
- 1757371
- PAR ID:
- 10338887
- Date Published:
- Journal Name:
- Journal of Dynamic Behavior of Materials
- ISSN:
- 2199-7446
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1007/s40870-022-00344-9
