CAREER: Engineered Dendritic Microstructures

Board Of Regents, Nshe, Obo University Of Nevada, Reno, Reno NV

Investigators

Abstract

This Career award to University of Nevada, Reno is to advance scientific understanding of dendritic solidification, and to apply this knowledge to improve modern metal casting methods. The principal technical goal of this effort is to use pressure oscillations, applied to a melt during solidification, to enhance the control over solidification morphologies during casting. Periodic pressure pulses will be applied during the casting process to stimulate the formation of dendrite secondary arms at a desired frequency, thereby establishing the secondary arm spacing that many important mechanical properties derive from. Cast samples will subsequently be characterized for key microstructural features (such as dendrite arm spacings) and mechanical properties (such as tensile strength). Educational and outreach programs of this Career award include the development of interdisciplinary science education, and the creation of computer-based learning modules that augment lectures and connect students in the classroom directly with the PI's research efforts. Additionally, the educational efforts will be leveraged by bringing local high school teachers into the lab during the summer, with the ultimate goal of developing new curricula for use in high schools. In metallurgy, dendritic (tree-like) crystal microstructures are the predominant morphological form of the cast microstructure. The characteristics of a dendritic microstructure are known to significantly affect many important material properties such as strength and ductility, which may be controlled to an extent by controlling the casting process. This award is to develop new parameters, which will significantly expand the range of control over cast microstructures and the resulting material properties. Pressure pulses will be utilized to stimulate the creation of regularly spaced dendrite branches with controlled properties. Education plans include the development of interdisciplinary science education, and the creation of computer-based learning modules that augment lectures and connect students in the classroom directly with research. Additionally, local high school teachers, during the summer, will participate in the ongoing research activities, and are encouraged to develop new curricula for use in their own classrooms.