Improved mechanical properties of thermoelectric (Bi0.2Sb0.8)2Te3 by nanostructuring

摘要

Temperature-dependent strength of Bi-Sb-Te under uniaxial compression is investigated. Bi-Sb-Te samples were produced by three methods: vertical zone-melting, hot extrusion, and spark plasma sintering (SPS). For zone-melted and extruded samples, the brittle-ductile transition occurs over a temperature range of 200-350?°C. In nanostructured samples produced via SPS, the transition is observed in a narrower temperature range of 170-200?°C. At room temperature, the strength of the nanostructured samples is higher than that of zone-melted and extruded samples, but above 300?°C, all samples decrease to roughly the same strength.