Creep behavior and post-creep thermoelectric performance of the n-type Skutterudite alloy Yb0.3Co4Sb12

Muath M. Al Malki, Xun Shi, Pengfei Qiu, G. Jeffrey Snyder, David C. Dunand*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

Abstract

Upon uniaxial compressive loading at 500 °C (T/Tm = 0.67, where Tm is the absolute melting point), the n-type Skutterudite alloy Yb0.3Co4Sb12 deforms plastically by creep via a power-law, with a stress exponent ∼3 consistent with dislocation viscous glide. An activation energy of 171 kJ/mol is measured over the temperature range of 500–587 °C (T/Tm = 0.67–0.75) at a stress of 30 MPa. Yb0.3Co4Sb12 is ductile at 500 °C, exhibiting a compressive strain of 25% when subjected to stresses ranging from 22 to 90 MPa for up to 28 days. Among the thermoelectric materials tested so far for creep, Yb0.3Co4Sb12 exhibits a creep resistance intermediate between low-melting (Bi2Te3, TAGS-85) and high-melting thermoelectrics (Mg2Si and ZrNiSn). A relatively modest drop in the figure of merit zT, from 0.67 to 0.52, is displayed by Yb0.3Co4Sb12 after accumulating 3.7% compressive creep strain at 500 °C, mostly due to a drop in electrical conductivity.

Original languageEnglish (US)
Pages (from-to)89-97
Number of pages9
JournalJournal of Materiomics
Volume7
Issue number1
DOIs
StatePublished - Jan 2021

Keywords

  • CoSb
  • Creep
  • Electrical conductivity
  • Filled Skutterudite
  • Seebeck coefficient

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Surfaces, Coatings and Films
  • Metals and Alloys

Fingerprint Dive into the research topics of 'Creep behavior and post-creep thermoelectric performance of the n-type Skutterudite alloy Yb<sub>0.3</sub>Co<sub>4</sub>Sb<sub>12</sub>'. Together they form a unique fingerprint.

Cite this