A structural and microstructural study was performed on several compositions of the Sm-y(FexNi1-x)(4)Sb-12 system treated at three different pressures during the spark plasma sintering (SPS) process. Aim of the study is to recognize the effect of applied pressure at a fixed temperature on composition, microstrain and domains size, due to the relevance of these parameters in driving the thermoelectric properties of the material. Increasing pressure induces a change in the Sm amount, as well as an increase in microstrain and a decrease in the diffraction domains size. At the same time, enhancing pressure above a certain threshold promotes the formation of the extra phase (Sm,Fe,Ni)Sb-2, and hence a large power factor reduction. Relying on data collected in this work, applying a pressure close to 180 MPa during SPS results to be a good compromise between advantages in terms of microstructure and transport properties, and disadvantages in terms of phase purity.
Effect of the sintering pressure on structure and microstructure of the filled skutterudite Sm-y(FexNi1-x)(4)Sb-12 (x=0.50-0.80, y=0.17-0.55)
Anselmi Tamburini, U;
2021-01-01
Abstract
A structural and microstructural study was performed on several compositions of the Sm-y(FexNi1-x)(4)Sb-12 system treated at three different pressures during the spark plasma sintering (SPS) process. Aim of the study is to recognize the effect of applied pressure at a fixed temperature on composition, microstrain and domains size, due to the relevance of these parameters in driving the thermoelectric properties of the material. Increasing pressure induces a change in the Sm amount, as well as an increase in microstrain and a decrease in the diffraction domains size. At the same time, enhancing pressure above a certain threshold promotes the formation of the extra phase (Sm,Fe,Ni)Sb-2, and hence a large power factor reduction. Relying on data collected in this work, applying a pressure close to 180 MPa during SPS results to be a good compromise between advantages in terms of microstructure and transport properties, and disadvantages in terms of phase purity.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
