The research objective of this Faculty Early Career Development (CAREER) Program project is to develop experimental and numerical tools to optimize the micro-hot embossing process for amorphous polymers. Hot embossing is used to impart micro-scale features to polymer surfaces and is important in the optical, electronics, automotive, and biomedical industries. The research will include an experimental investigation of the effects of surface characteristics in processing, and the results will be used to develop and validate new finite element simulations of hot embossing. Hot embossing is one of many processes that take place near the glass transition temperature. Current experimental data and constitutive models in this temperature range are limited, restricting the design of hot embossing to costly iterative approaches. This research aims to address these needs through material characterization and modeling near the glass transition temperature, process-level finite element modeling, and lab-scale embossing experiments for model validation. The educational objective is to integrate the research into existing engineering courses and to develop outreach methods to promote technical awareness and interest in engineering among 8th grade students.
If successful, the results of this research will advance the state of the art in polymer manufacturing by (1) generating new experimental data for polymers near the glass transition, an industrially important temperature range with limited published data; (2) developing a new constitutive model to capture thermoplastic behavior over a wide range of temperatures across the glass transition; (3) providing computational modeling tools for design and optimization of micro-hot embossing; and (4) providing experimental insight into the role of micro-scale surface features in hot embossing. Hot embossing is an environmentally-friendly alternative for creating surface features and the developed design tools will facilitate the push toward nano-scale features. The integration of research and education through this award will provide tangible exposure to cutting-edge research through projects imbedded in undergraduate finite element and graduate polymer processing courses.