Influence of Temperature During Spark Plasma Sintering Compaction of Melt-Spun p-Bi0.5Sb1.5Te3

Abstract

The melt spinning technique is a process for obtaining materials based on ultrafast cooling and solidification of a melt in contact with a liquid-cooled rotating wheel. In this work, p-Bi0.5Sb1.5Te3 powders were obtained and compacted by spark plasma sintering at various temperature conditions, and the changes in their structural and dimensional characteristics were investigated. It is shown that the sintering temperature conditions significantly affect the structure of the material, causing active recrystallization processes even at short sintering times (5 min to 10 min). Material obtained in this work has slight preferential orientation of (0 0 1) planes perpendicular to the pressure axis, which disappears with increasing sintering time. Power factor values for all samples were greater for current direction perpendicular to the pressure axis, which corresponds to compacted nonspun material. It is shown that annealing in vacuum negatively affects the material, reducing the power factor for all current directions.