Please consider attending the following:
MATERIALS ENGINEERING
“Grain Growth Rate Transitions in Barium Strontium
Titanate”
By
Matthew J. Michie
Purdue MSE Ph.D. Final Exam
Advisors: Professor Carol A. Handwerker and Professor John E. Blendell
ABSTRACT
Understanding grain growth of dielectric ceramics is essential to controlling the electrical and mechanical properties necessary to produce ceramic capacitors and sensors. The
effect of alloying barium titanate with strontium titanate on the equilibrium crystal shape is being investigated in order to determine possible impacts on grain growth. The equilibrium crystal shape is being studied through three experimental methods to identify
possible changes in the mobility or driving force with changing composition. The first method is by imaging intergranular pores to observe faceting behavior and relative interfacial energies. The second method is to perform atomic force microscopy on surface
facets to collect topography data. The topography data is combined with orientation data obtained by EBSD analysis from the same region and is used to calculate the normal vector of the surface facets. The normal vectors are plotted in a stereographic projection
to verify the faceting relationships observed in the pore shape analysis. The third method involves collecting EBSD orientation data and images of surface faceting behavior. The surface faceting behavior of each grain is categorized by type of facet and plotted
on a stereographic projection at the corresponding orientation. This allows for the analysis of faceting transitions and the differentiation of faceted and continuous regions of the equilibrium crystal shape. The analysis of the equilibrium crystal shape of
across compositions has implications on grain growth of the barium titanate/strontium titanate system.
Date: Wednesday, July 17, 2019
Time: 9:00 A.M.
Place: ARMS 3109