Thermal expansion behaviors of LAST and LASTT thermoelectric materials as a function of temperature

Conference · Tue Jan 01 04:00:00 EST 2008

OSTI ID:968256

Trejo, Rosa M ^[1]; Case, Eldon D ^[2]; Lara-Curzio, Edgar ^[1]; Ren, Fei ^[2]; Timm, Edward J ^[2]; Hall, Bradley D. ^[2]

---

1. ORNL
2. Michigan State University, East Lansing

LAST (Pb-Sb-Ag-Te) and LASTT (Pb-Sb-Ag-Te-Sn) materials exhibit good thermoelectric (TE) properties, which can be potentially applied in waste heat recovery. Thermal expansion behavior of TE materials is critical to the fabrication and performance of TE devices, which are subject to temperature gradients and/or thermal cycling under in-service conditions. In this study, the coefficient of thermal expansion (CTE) of LAST and LASTT fabricated by both casting and hot pressing were determined via thermomechanical analysis between room temperature (RT) and 673 K. In addition, the lattice parameters of LAST materials were calculated from high temperature X-ray diffraction patterns obtained between RT and 623 K. The mean CTE values ranged between 20 x 10-6 K-1 and 23 x 10-6 K-1. While the temperature dependent CTE of Ag0.43Pb18Sb1.2Te20 composition increased with increasing temperature, a peak between RT and 450 K in the CTE versus temperature curve was observed for the Ag0.86Pb19SbTe20 concentration.

• Research Organization: Oak Ridge National Laboratory (ORNL); High Temperature Materials Laboratory
• Sponsoring Organization: EE USDOE - Office of Energy Efficiency and Renewable Energy (EE)
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 968256
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CASTING
CTE
FABRICATION
HOT PRESSING
LATTICE PARAMETERS
PERFORMANCE
TEMPERATURE GRADIENTS
THERMAL CYCLING
THERMAL EXPANSION
THERMOELECTRIC MATERIALS
Thermoelectric
WASTE HEAT
X-RAY DIFFRACTION
thermal expansion