Methodology for Obtention of Cross Sectional Images for Microwire Crystal Size Determination

Authors: Talia Ruoff, Ahmed Abdelrazaq Saleh Alajlouni

Field of Study: Science, Technology, Engineering, and/or Math

Faculty Mentors: Jingzhou Zhao

Easel: 15

Timeslot: Midday

Abstract: Polycrystalline SAC 305 thermoelectric microwire is produced and analyzed via novel methodology. This study will focus on the grinding method to obtain cross-sectional views of the microwire in order to visualize the internal crystalline structure. First, a bundle of the microwires are sealed in resin, forming a circular puck shape, with the microwires in the center. The flat side of the puck is then ground using a 370-M-Prep manual polisher until no grooves are visible on the microwire cross section at 1000x magnification. Finally, images are captured of the smooth microwire cross section. From these images, crystal diameter and frequency are determined. Parameters such as cooling rate and pulling speed will be adjusted and crystal grain diameter will be observed in order to determine the perfect method to improve electrical conductivity, minimize diameter, and avoid capillary instability and breakage.