Shrinking from the Heat: Negative Thermal Expansion Materials

Department of Chemical Engineering and Materials Science Seminar

Featuring Cora Lind, Ph.D.
Assistant Professor, Chemistry
University of Toledo

Location:  Engineering Lecture Hall 110
Free and open to the public.
Light refreshments served following the event.

Abstract:
Negative thermal expansion (NTE) materials have received considerable scientific interest because of their potential for use as fillers in composites. Mixing of a positive thermal expansion material with a NTE filler should reduce the overall expansion coefficient of the composite while maintaining other desirable properties of the matrix material.

Dedicated research on NTE materials started only during the last decade. Much progress has been made in the synthesis and characterization of NTE compounds, but many show properties like irreversible phase transitions under pressure that could interfere with the processing of composites. In addition, a number of NTE oxides are metastable, thus requiring synthetic approaches that use kinetic control.

In this talk, a brief overview of important aspects relating to the field of NTE research will be given. Lind will then focus on synthetic approaches to new NTE materials. The materials are characterized by variable temperature X-ray and neutron powder diffraction experiments and in-situ high-pressure diffraction studies. Finally, some first results on the preparation of NTE/polymer composites will be discussed.

Assistant Professor Cora Lind was nominated for the American Chemical Society’s PROGRESS/Dreyfus lectureship award which identifies her as a “rising star” at Carnegie Research Extensive Universities, and provides for her to travel to lecture at other universities. Lind was also voted a member of the U.S. National Committee for Crystallography, and she will receive the 2007 Margaret C. Etter Earlty Career Award from the American Crystallographic Association. The Etter award recognizes “outstanding achievement and exceptional potential in crystallographic research demonstrated by a scientist at an early state of their independent career.”