[SIT31-05] Sound velocity of B2-FeNiSi alloy at high pressure determined with inelastic X-ray scattering: Implications for the composition of the Earth's inner core
Keywords:Sound velocity, Inner core, B2-FeNiSi alloy, High Pressure, Inelastic X-ray scattering
We measured the sound velocity of Fe78Ni7Si15 alloy with a B2 structure at room temperature up to 90 GPa employing inelastic X-ray scattering to constrain the constitution of the inner core. The density of the alloy was also determined by X-ray diffraction under the same conditions. The relation of the P-wave velocity (vP) and density (ρ) of B2-Fe78Ni7Si15 alloy follows Birch’s law. We discuss the possibility that the inner core is composed of the B2-Fe78Ni7Si15 alloy or the mixture of hcp and B2 alloys based on Birch’s law determined here for B2-Fe78Ni7Si15 alloy and that for hcp-Fe and FeSi alloys reported previously [3, 4]
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