Spark plasma sintered bismuth telluride-based thermoelectric materials incorporating dispersed boron carbide

Abstract

The mechanical properties of bismuth telluride based thermoelectric materials have received much less attention in the literature than their thermoelectric properties. Polycrystalline p-type Bi 0.5 Sb 1.5 Te 3 materials were produced from powder using Spark Plasma Sintering (SPS). The effects of nano-B 4 C addition on the thermoelectric performance, Vickers hardness and fracture toughness were measured. Addition of 0.2 vol% B 4 C was found to have little effect on zT but increased hardness by approximately 27% when compared to polycrystalline material without B 4 C. The K IC fracture toughness of these compositions was measured as 0.80 MPa m 1/2 by Single-Edge V-Notched Beam (SEVNB). The machinability of polycrystalline materials produced by SPS was significantly better than commercially available directionally solidified materials because the latter is limited by cleavage along the crystallographic plane parallel to the direction of solidification.

Effect of Ga2O3 Nanoparticles Dispersion on Microstructure and Thermoelectric Properties of p-Type BiSbTe Based Alloys

“…Also, the distributed Ga 2 O 3 nanoparticles could increase the hardness due to dispersion strengthening mechanism. The present work shows improved hardness than other Bi-Te based nanocomposites reported elsewhere [15,16].…”

“…It is clearly shown in Figure 5 nanocomposites. In general, the electrical conductivity is given by [16],…”

Mechanical properties and microstructure of spark plasma sintered nanostructured p-type SiGe thermoelectric alloys

“…This nanostructured alloy exhibited a hardness of ~ 9 ± 0. alloy compared with other state-of-the-art thermoelectric materials, such as Bi 2 Te 3 , [33] Bi 2 Te 3 +0.1Vol.%SiC [33],LAST [78], Bi 0.5 Sb 1.5 Te 3 +0.2Vol.%B 4 C [79], PbTe+PbS [80], Cu 3 SbSe 3 and Cu 3 SbSe 4 [34], Cu 2 Se [52], Co 4 Sb 12 [35], In 0.1 Co 4 Sb 12 [35], n-type nanostructured Si 80 Ge 20 alloys [29,30]. [36], PbTe [36] and ntype nanostructured Si 80 Ge 20 alloy [29].…”

European Radioisotope Thermoelectric Generators (RTGs) and Radioisotope Heater Units (RHUs) for Space Science and Exploration

“…A number of generations and variations of bismuth telluride based thermoelectric converters or generators (TEGs) have been produced for the RTG system (Mesalam et al 2018Williams et al 2014). Americium-based nuclear power systems have lower power densities and occupy larger volumes for equivalent power outputs than Pu-based systems and offer the option of targeting lower operational temperatures Barco et al 2019a).…”

“…These devices were optimised for this specific programme. Commercial standard production methods were used Williams et al (2014), for example, on modifying the thermoelectric materials by the addition of boron carbide, has resulted in improvements in mechanical properties without negatively impacting on thermoelectric properties.…”