Dartmouth Engineering professor Yan Li and research associate Chi Ma developed the computational framework to account for the atomic structure evolution of PDCs while they undergo pyrolysis, a type of heat treatment, and their resulting transformation.

"The polymer-to-ceramic transition opens up exciting opportunities to produce a broad spectrum of PDCs with tailored mechanical, chemical, and physical properties," said Li, corresponding author of the study. "Importantly, shaping at the polymer state can avoid problems related to tool wear and brittle fracture upon finishing the ceramic component."

The paper, "Modeling of Phase Transition in Fabrication of Polymer-Derived Ceramics (PDCS)," was published yesterday by the International Journal of Computational Materials Science and Engineering. It specifically investigated polymethylhydrosiloxane (PMHS) crosslinked by divinylbenzene (DVB), but the approach itself can be applied to other PDC fabrication systems.

"We found that heating rate, pyrolysis temperature, and pyrolysis time combine to affect the mechanical response of the pyrolyzed sample," said Li. "Certain phase composition maps can lead to improved material strength without sacrificing the ductility. These additional capabilities will greatly extend the use of ceramics in areas such as biomedical implants and renewable energy storage devices, where customer-specific geometry and functionality are in high demand."

The research was supported by funding from the NH Center for Multiscale Modeling and Manufacturing of Biomaterials (NH BioMade), a five-year, $20 million Established Program to Stimulate Competitive Research (EPSCoR) project funded by the National Science Foundation (NSF). The research also utilized Dartmouth start-up funds.