Density of liquid iron alloy under high pressure is important to constrain the amount of light elements in the Earth's core. Density measurement of solid and liquid Fe3C was performed using X-ray absorption image technique up to 9.5 GPa and 1973 K. Density of liquid Fe3C increases from 6.94 g/cm3 to 7.38 g/cm3 with a pressure of 3.6-9.5 GPa at 1973 K. The bulk modulus of liquid Fe3C is obtained to be 50 ± 7 GPa at 1973 K. The effect of carbon on the compressibility of liquid iron is similar to that of sulfur, which significantly decreases the bulk modulus of liquid iron. Since carbon dissolution into liquid iron causes reduction of ρ and K0T, carbon could be excluded from the candidates of alloying light elements in the Earth's outer core.
ASJC Scopus subject areas
- Geochemistry and Petrology
- Earth and Planetary Sciences (miscellaneous)
- Space and Planetary Science