The compressive creep behavior of hot-pressed Mg1.96Al0.04Si0.97Bi0.03, a promising thermoelectric material, is investigated at 500 °C. At stress levels between 81 and 212 MPa, dislocation creep with stress exponent n = 7.6 ± 0.3 is observed. No diffusional creep is observed, likely attributable to a dispersion of ~1 μm Bi-, Al-, and O- rich particles which pin grain boundaries. Mg1.96Al0.04Si0.97Bi0.03 exhibits similar creep behavior to previously studied silicides, but is significantly more creep resistant than other thermoelectric materials, PbTe and Bi2Te3. This makes Mg1.96Al0.04Si0.97Bi0.03 an excellent material for thermoelectric power generation systems subjected to high stresses and temperatures.
Bibliographical noteFunding Information:
This work made use of the MatCI Facility which receives support from the MRSEC Program (NSF DMR-1121262) of the Materials Research Center at Northwestern University. This work made use of the EPIC facility of Northwestern University's NUANCE Center, which has received support from the MRSEC program (NSF DMR-1121262) at the Materials Research Center; the International Institute for Nanotechnology (IIN); and the State of Illinois, through the IIN. WL thanks the Grant ( 2017R1A2A1A17069528 ) and Priority Research Centers Program (2009-0093823) funded by National Research Foundation of Korea (NRF) and Hyundai Motor Company ( 2016-11-0532 ).
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering
- Metals and Alloys