Strain Analysis of Thermoelectric Materials Using High-resolution Synchrotron X-ray Diffraction Data

Abstract

A compressive strength limit is one of critical parameters for thermoelectric materials. In this study, we synthesized a single crystal of Yb-filled Co–Sb based skutterudite. We assessed the compressive pressure dependence of internal strain using high-resolution synchrotron radiation X-rays at SPring-8. The prepared single crystal was identified as Yb_0.148Co₄Sb_12.54, with a lattice parameter of 9.0504 Å. Compressive testing was performed until the sample fractured, revealing a compressive strength limit of 591.3 MPa. The stress–strain curve exhibited a nearly constant slope for strains exceeding 0.07%, leading to an estimated Young’s modulus of 154.6 GPa.