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This content will become publicly available on July 1, 2023

Title: 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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Journal of Dynamic Behavior of Materials
Sponsoring Org:
National Science Foundation
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